Patent Publication Number: US-2002007546-A1

Title: Advanced alloy fiber and process of making

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] This invention relates to metallic alloys, and more particularly to an improved process for producing metallic alloys in the forms of a metallic alloy fiber. This invention relates further to the production of a fine metallic alloy fiber formed from a new alloy and/or a fine metallic alloy fiber having different surface properties.  
       [0003] 2. Background of the Invention  
       [0004] Metallic alloys have been utilized in many applications of use over pure metals due to the many desirable qualities of metallic alloys. Many metallic alloys exhibit the desirable qualities of a higher melting point, a greater hardness, and a greater chemical stability relative to pure metals. Typically, metallic alloys are high strength materials. Many metallic alloys have a high tolerance for corrosion resistance making metallic alloys desirable for use in hostile environments and the like. In addition, metallic alloys typically have high melting points making the metallic alloys desirable for high temperature applications. Unfortunately, some corrosion resistant and heat resistant metallic alloys exhibit low ductility and low-temperature brittleness.  
       [0005] Metallic alloys are metallic solid solutions formed from two or more dissimilar metals. The two or more dissimilar metals are heated to diffuse or melted together to convert the dissimilar metals into the solid solution. The metallic alloys are typically formed by powder metallurgy methods or by melt processing of stoichiometric single crystals.  
       [0006] Metallic alloys may be formed by mixing two or more dissimilar powdered metals. The mixed powders are heated to diffuse or melt together dissimilar metals to convert the dissimilar metals into the metallic alloy. After the conversion into the metallic alloy, the low ductility and low-temperature brittleness of the metallic alloy makes the metallic alloy difficult to deform, mold or machine.  
       [0007] In many cases, the dissimilar powdered metals are formed into a general shape of the desired item prior to converting the dissimilar powdered metals into the metallic alloy. This formation of the dissimilar powdered metals into the general shape of the desired item, overcomes the difficulty in deforming, molding or machining after conversion into the metal alloy.  
       [0008] In addition to the powder metallurgy methods set forth above, metallic alloys may be formed by the melt processing of stoichiometric single crystals. Unfortunately, neither of these methods is suitable for the formation of alloy wire. The low ductility and low-temperature brittleness of these metallic alloys made the production of metallic alloy wire a perplexing task. Furthermore, the low ductility and low-temperature brittleness of metallic alloy wire made the subsequent processing such as a successive wire drawing process of a metallic alloy wire a futile endeavor. Although small wires can be formed with metallic alloys, fine alloy fibers have heretofore not been formed due to the difficulty of drawing alloy wires into alloy fibers in a successive wire drawing process.  
       [0009] Many in the prior art have attempted to form very small alloy wire notwithstanding the difficulty of drawing alloy wires in a wire drawing process. Some representative prior art processing of metallic alloy wires is set forth in the following United States Patents.  
       [0010] U.S. Pat. No. 2,215,477 to Pipkin discloses a method of manufacturing wires of a relatively brittle metal which consists of assembling a rod of the metal within a tube of a relatively ductile metal to form therewith a composite single assembly. The assembly is successively drawn through a series of dies to thereby form a composite wire elements. A plurality of the wire elements are assembled within a tube of metal of the same character as that of the first-named tube to form therewith a composite multiple assembly. The multiple assembly is successively drawn through a series of dies to reduce the same to a predetermined diameter. The ductile metal is removed from the embedded wires of brittle metal.  
       [0011] U.S. Pat. No. 2,434,992 to Durst discloses an electrical contact comprising a length of a fine wire of valuable electrically conductive metal. The wire has a small cross-section and is encased in a sheath. The wire is mounted on an electrically conductive base in electrically conductive relation with respect thereto by means of an intermediate wire-supporting member of a non-valuable electrically conductive metal with the length of wire extending substantially parallel to and spaced outward from the base. The electrical outlet contact is formed by welding the sidewise periphery of a sheath for the wire of a non-valuable electrically conductive metal to the base and etching away all of the sheath except a portion intermediate the base and wire constituting the intermediate wire-supporting member. The base is formed of a metal which is resistant to etching by at least one etching agent which will etch the non-valuable metal of the sheath so that the base is not substantially etched away during the etching of the sheath.  
       [0012] U.S. Pat. No. 3,363,304 to Quinlan discloses exceedingly brittle zirconium-beryllium eutectic (about 5% Be by weight) made into a wire by enclosing it in a heavy stainless steel capsule and rotary swaging the assembly. The swaging is carried out at a temperature in the range 775-800 C. until the diameter has been reduced about 50%. The temperature is lowered to 700-735 C. for the remainder of the swaging. If wire rings are desired, the composite wire is wound on a mandrel while at its elevated temperature to form a helix. The stainless steel sheath is dissolved in sulfuric acid and the turns of the helix cut apart. A Zr—Be rod one half inch in diameter has been reduced to a wire 0.025 inch in diameter.  
       [0013] U.S. Pat. No. 3,394,213 to Roberts et al. discloses a method of forming fine filaments under approximately 15 microns in long lengths wherein a plurality of sheathed elements are firstly constricted to form a reduced diameter billet by means of hot forming the bundled filaments. After the hot forming constriction, the billet is then drawn to the final size wherein the filaments have the desired final small diameter. The material surrounding the filaments is then removed by suitable means leaving the filaments in the form of a tow.  
       [0014] U.S. Pat. No. 3,540,114 to Roberts et al. discloses a method of forming fine filaments formed of a material such as metal by multiple end drawing a plurality of elongated elements having thereon a thin film of lubricant material. The plurality of elements may be bundled in a tubular sheath formed of drawable material. The lubricant may be applied to the individual elements prior to the bundling thereof and may be provided by applying the lubricant to the elements while they are being individually drawn through a coating mechanism such as a drawing die. The lubricant comprises a material capable of forming a film having a high tenacity characteristic whereby the film is maintained under the extreme pressure conditions of the drawing process. Upon completion of the constricting operation, the tubular sheath is removed. If desired, the lubricant may also be removed from the resultant filaments.  
       [0015] U.S. Pat. No. 3,785,036 to Tada et al. discloses a method of producing fine metallic filaments by covering a bundle of a plurality of metallic wires with an outer tube metal and drawing the resultant composite wire. The outer tube metal on both sides of the final composite wire obtained after the drawing step is cut near to the core filaments present inside the outer tube and then both uncut surfaces of the composite wire are slightly rolled, thereby to divide the outer tube metal of the composite wire continuously and thus separating the outer tube metal from fine metallic filaments. The separation treatment can be effected by a simple apparatus within short time. This reduces the cost of production, and enables the outer tube metal to be recovered in situ.  
       [0016] U.S. Pat. No. 3,807,026 to Takeo et al. discloses a method of producing a yarn of fine metallic filaments at low cost, which comprises covering a bundle of a plurality of metal wires with an outer tube metal to form a composite wire. The composite wire is drawn and the outer tube metal is separated from the core filaments in the composite wire. The surfaces of the metal wires are coated with a suitable separator or subjected to a suitable surface treatment before the covering of the outer tube metal, thereby to prevent the metallic bonding of the core filaments to each other in the subsequent drawing or heat-treatment of the composite wire.  
       [0017] U.S. Pat. No. 3,838,488 to Tada et al. discloses an apparatus for producing fine metallic filaments which comprises supply means for supplying a drawn composite wire comprising a bundle of a plurality of metallic filaments surrounded by an outer metal tube. A cutting means comprising cutting bits is arranged symmetrically with respect to the composite wire in the cutting means for cutting and removing most of the outer metal tube of the composite wire on opposite sides of the metal tube. A rolling means comprises oppositely disposed rolls for pressing the uncut sides of the composite wire and to cause the composite wire to be compressed and spread outwardly in a direction perpendicular to the cut sides of the metal tube and for causing the metal tube to divide at the cut surface. A pickup means takes up the divided parts of the metal tube and the metallic filaments.  
       [0018] U.S. Pat. No. 3,848,319 to Hendrickson discloses the procedure for fabricating ultra-small precious metal or metal alloy wire comprising the steps of fabricating and annealing a copper sleeve with an axially aligned opening formed therein. A precious metal core is formed and inserted into the opening of the sleeve. The sleeve and the core have an outer dimensions preferably formed in the ratio of ten to one for mechanically binding the core to the sleeve to produce a bimetallic wire combination. The size of the wire combination is reduced on suitable wire drawing dies and the sleeve is chemically removed from the precious metal wire.  
       [0019] U.S. Pat. No. 3,943,619 to Hendrickson discloses a procedure for drawing ultrafine wires which incorporates the steps of inserting a core wire of a selected material into a plurality of telescoped sacrificial sheaths, welding the ends of the core wire to the sheath and successively drawing the combination down to a predetermined diameter. The outside sheath is sacrificed by etching to free the proportionately reduced core wire. The core wire may be initially covered with Teflon to aid in the reduction and the Teflon is removed by exposure to heat.  
       [0020] U.S. Pat. No. 3,977,070 to Schildbach discloses a method of forming a tow of filaments and the tow formed by the method wherein a bundle of elongated elements, such as rods or wires, is clad by forming a sheath of material different from that of the elements about the bundle and the bundle is subsequently drawn to constrict the elements to a desired small diameter. The elements may be formed of metal. The bundle may be annealed, or stress relieved, between drawing steps as desired. The sheath may be formed of metal and may have juxtaposed edges thereof welded together to retain the assembly. The sheath is removed from the final constricted bundle to free the filaments in the form of tow.  
       [0021] U.S. Pat. No. 4,044,447 to Hamada et al. discloses a number of wires gathered together and bound with an armoring material in the shape of a band. The wires in this condition are drawn by means of a wire drawing apparatus having dies and a capstan. A plurality of bundles of such wires are gathered together and bound in the same way as in the foregoing to form a composite bundle body, which is further drawn, and these processes are repeated until at least filaments of a specified diameter are obtained in quantities.  
       [0022] U.S. Pat. No. 4,209,122 to Hunt discloses a method of manufacturing wire described as alloy rods in an as cast condition and incorporated into a filled billet which is extruded within defined extrusion parameters to obtain a simultaneous reduction in the diameters of the cast rods. After separation from the filled billet, the extruded rods, now in wire form, are particularly suitable for manual welding applications of hard facing deposits. The separated alloy wires are joined by butt welding to form a wire of indeterminable length which is accurately sized by successive drawing and annealing steps, making it suitable for use with an automatic welding machine to weld hard facing deposits.  
       [0023] U.S. Pat. No. 4,323,186 to Hunt discloses a method for obtaining extrusion products of alloy wire of small cross section in an economical fashion. The ratio of length to cross section of cast alloy preforms limits the length of a filled billet to less than the optimum which may be extruded on available extrusion presses where it is desired to obtain small diameter extrusion products in a single extrusion. This limitation is overcome by squaring the ends of cast lengths of the alloy and then butt welding such lengths to compositely form preforms of the maximum length capable of being extruded on a given extrusion press. The composite preforms are extruded in a filled billet in accordance with the teaching of U.S. Pat. No. 4,209,122. The extrusion products from these composite preforms have the same desirable properties described in that patent and extend the benefits described therein.  
       [0024] U.S. Pat. No. 4,863,526 to Miyagawa et al. discloses a fine crystalline thin wire of a cobalt base alloy and a process of making having a composition of the formula CokMlBmSin where Co is cobalt; M is at least one of the transition metals of groups IV, V and VI of the periodic table; B is boron; Si is silicon; K, 1, m and n represent atom percent of Co, M, B and Si, respectively and the fine crystal grains in the thin wire having an average size of no more than 5 μm.  
       [0025] U.S. Pat. No. 5,266,279 to Haerle discloses a filter or catalyst body for removing harmful constituents from the waste gases of an internal combustion engine provided with at least one fabric layer of metal wires or metal fibers. Sintering material in the form of powder, granules, fiber fragments or chips is introduced into the meshes and is sintered on to the wires or fibers. The woven fabric is in the form of a twilled wire fabric, sintering material being introduced into the meshes thereof and being sintered together with the wires or fibers.  
       [0026] U.S. Pat. No. 5,505,757 to Ishii discloses a metal filter for a particulate trap which meets the requirements for low pressure drop, high collecting capacity and a long life. The metal filters have one or more layers of unwoven fabric (such as felt) formed of a metal fiber having one of the following alloy compositions A, B and C wherein composition A is made of Ni:5-20% by weights, Cr:10-40 by weights, Al:1-15% by weight, the remainder being Fe and inevitable impurities; composition B is made of Cr:10-40% by weight, Al:1-15% by weight, the remainder being Ni and inevitable impurities; and composition C is made of Cr:10-40% by weight, Al:1-15% by weight, the remainder being Fe and inevitable components. The metal filter is highly resistant to corrosion and heat and can withstand repeated heating for removal of the particulate.  
       [0027] U.S. Pat. No. 5,827,997 to Chung et al. discloses a material including filaments, which include a metal and an essentially coaxial core, each filament having a diameter less than 6 um, each core being essentially carbon, displays high effectiveness for shielding electromagnetic interference (EMI) when dispersed in a matrix to form a composite material. This matrix is selected from the group consisting of polymers, ceramics and polymer-ceramic combinations. This metal is selected from the group consisting of nickel, copper, cobalt, silver, gold, tin, zinc, nickel-based alloys, copper-based alloys, cobalt-based alloys, silver-based alloys, gold-based alloys, tin-based alloys and zinc-based alloys. The incorporation of 7 percent volume of this material in a matrix that is incapable of EMI shielding results in a composite that is substantially equal to copper in EMI shielding effectiveness at 1-2 GHz.  
       [0028] U.S. Pat. No. 5,830,415 to Maeda et al. discloses a car exhaust purifying filter member which is high in the capacity to collect solid and liquid contents in exhausts and which has such high heat resistance as to be capable of withstanding heat when burned for cleaning and a method of manufacturing the same. A three-dimensional mesh-like metallic porous member made from Ni—Cr—Al and having a three-dimensional frame-work is heated to 800-100 degrees C. in the atmosphere to form on its surface a densely grown fibrous alumina crystal. This member is used as a filter member. Such a filter member shows excellent collecting capacity and corrosion resistance and can withstand high temperatures. Also, it is possible to firmly carry a catalyst on the fibrous alumina crystal formed on the surface. Because of its increased surface area, it has an increased catalyst carrying capacity.  
       [0029] U.S. Pat. No. 5,863,311 to Nagai et al. discloses a particulate trap for a diesel engine use which is less likely to vibrate or deform under exhaust pressures and achieves good results in all of the particulate trapping properties, pressure drop, durability and regenerating properties. This trap has a filter element made of plurality of flat or cylindrical filters. Longitudinally extending exhaust incoming and outgoing spaces are defined alternately between the adjacent filters by alternately closing the inlet and outlet ends of the spaces between the adjacent filters. Gas permeable reinforcing members are inserted in the exhaust outgoing spaces to prevent the filter from being deformed due to the difference between the pressure upstream and downstream of each filter produced when exhausts pass through the filters. Similar gas permeable reinforcing members may also be inserted in the exhaust incoming spaces or at both ends of the filter element to more positively prevent vibration of the filters.  
       [0030] U.S. Pat. No. 5,890,272 to Liberman et al. discloses a process for making fine metallic fibers comprising coating a plurality of metallic wires with a coating material. The plurality of metallic wires are jacketed with a tube for providing a cladding. The cladding is drawn for reducing the outer diameter thereof The cladding is removed to provide a remainder comprising the coating material with the plurality of metallic wires contained therein. The remainder is drawn for reducing the diameter thereof and for reducing the corresponding diameter of the plurality of metallic wires contained therein. The coating material is removed for providing the plurality of fine metallic fibers.  
       [0031] U.S. Pat. No. 5,908,480 to Ban et al. discloses a particulate trap for use in a diesel engine which is inexpensive, and which is high in particulate trapping efficiency, regeneration properties and durability, and low in pressure loss due to particulates trapped. An even number of flat filters made from a non-woven fabric of heat-resistant metallic fiber are laminated alternately with the same number of corrugated sheets made of a heat-resistant metal. The laminate thus formed are rolled into a columnar shape. Each space between the adjacent flat filters in which every other corrugated sheet is inserted is closed at one end of the filter element by a closure member. The other spaces between the adjacent flat filters are closed at the other end of the filter element.  
       [0032] U.S. Pat. No. Re. 28,470 to Webber discloses a porous metal structure made from a plurality of relatively short fracture-free substantially non-straight rough surfaced metal fibers distributed in either a two-dimensional or a three-dimensional orientation. The fibers have preselected cross sections with the porous structure containing either uniform cross-section fibers or different cross-sectioned fibers. The fibers may be in a stress relieved condition or a cold worked condition. The porous metal structure fibers have a mean cross-sectional dimension of under approximately fifty microns and the fibers have an average length of at least approximately two inches.  
       [0033] Although small wires can be formed with metallic alloys, fine fibers formed from metallic alloys have heretofore not been formed due to the difficulty of drawing alloy wires into metallic alloy fine fibers in a wire drawing process.  
       [0034] Therefore, it is an object of the present invention to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy.  
       [0035] Another object of the present invention is to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy wherein the fine metallic alloy fiber has a diameter less than fifty microns.  
       [0036] Another object of the present invention is to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy which is capable of making a fine fiber made from a new metallic alloy.  
       [0037] Another object of the present invention is to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy having different surface properties.  
       [0038] Another object of the present invention is to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy that is economical to manufacture.  
       [0039] Another object of the present invention is to provide a fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy that is cost effective for producing fine fibers from a metallic alloy in commercial quantities.  
       [0040] The foregoing has outlined some of the more pertinent objects of the present invention. These objects should be construed as being merely illustrative of some of the more prominent features and applications of the invention. Many other beneficial results can be obtained by applying the disclosed invention in a different manner or modifying the invention with in the scope of the invention. Accordingly other objects in a full understanding of the invention may be had by referring to the summary of the invention, the detailed description describing the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.  
       SUMMARY OF THE INVENTION  
       [0041] The present invention is defined by the appended claims with specific embodiments being shown in the attached drawings. For the purpose of summarizing the invention, the invention relates to a process for making a fine metallic alloy fiber comprising the steps of encompassing a metallic alloy wire with a cladding material. The cladding material is tightened about the metallic alloy wire in the presence of an inert atmosphere to provide a cladding. The cladding is drawn for reducing the outer diameter thereof and for reducing the diameter of the metallic alloy wire to provide a fine metallic alloy fiber from the metallic alloy wires. The cladding material is removed from the fine metallic alloy fiber.  
       [0042] In a more specific example of the invention, the step of tightening the cladding material about the metallic alloy wire comprises tightening the cladding material about the metallic alloy wire in the presence of an inert atmosphere located between the cladding material and the metallic alloy wire. The step of drawing the cladding includes successively drawing and successively annealing the cladding at a temperature between 1650° F. and 2050° F. and rapidly cooling the cladding in a heat conducting fluid after the annealing process.  
       [0043] In another example of the invention, the process includes assembling a multiplicity of the drawn claddings within a second cladding material to form a second cladding. The second cladding are drawn for reducing the diameter thereof and for providing a multiplicity of fine metallic alloy fibers from the multiplicity of metallic alloy wires. The cladding materials are removed for providing a multiplicity of fine metallic alloy fibers.  
       [0044] In another example of the invention, the process includes providing a metallic alloy wire formed from a first and a second alloy component with the cladding material being formed from one of the first and second alloy components. The metallic alloy wire encompassed with the cladding material to provide a cladding. The cladding is drawn for reducing the outer diameter thereof and for reducing the diameter of the metallic alloy wire to provide a drawn cladding having a fine metallic alloy fiber formed from the metallic alloy wire. The drawn cladding is heated to a temperature sufficient for annealing the drawn cladding with minimal diffusion of the cladding material into the fine metallic alloy fiber. The cladding material is removed from the fine metallic alloy fiber and the fine metallic alloy fiber is heated to a temperature sufficient to further diffuse the minimal diffused cladding material into the metallic alloy fiber to provide a substantially homogeneous fine metallic alloy fiber.  
       [0045] In another example of the invention, the cladding material is formed from a material different from the first and second alloy components. The cladding is drawn for reducing the outer diameter thereof and for reducing the diameter of the metallic alloy wire to provide a drawn cladding having a fine metallic alloy fiber formed from the metallic alloy wire. The drawn cladding is heated to a temperature sufficient for annealing the drawn cladding and for diffusing the cladding material into the metallic alloy fiber. The cladding material is removed from the fine metallic alloy fiber. The fine metallic alloy fiber is heated to a temperature sufficient to further diffuse the diffused cladding material into the metallic alloy fiber to provide a fiber formed from a new alloy comprising the first and second alloy component and the diffused cladding material.  
       [0046] In another example of the invention, the cladding material is formed from a material different from the first and second alloy components. The drawn cladding is heated to a temperature sufficient for annealing the drawn cladding and for diffusing the cladding material into the surface of the metallic alloy fiber. The cladding material is removed for providing a fine metallic alloy fiber having surface properties in accordance with the properties of the cladding material.  
       [0047] The foregoing has outlined rather broadly the more pertinent and important features of the present invention in order that the detailed description that follows may be better understood so that the present contribution to the art can be more fully appreciated. Additional features of the invention will be described hereinafter which form the subject of the claims of the invention. It should be appreciated by those skilled in the art that the conception and the specific embodiments disclosed may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present invention. It should also be realized by those skilled in the art that such equivalent constructions do not depart from the spirit and scope of the invention as set forth in the appended claims.  
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0048] For a fuller understanding of the nature and objects of the invention, reference should be made to the following detailed description taken in connection with the accompanying drawings in which:  
     [0049]FIG. 1 is a block diagram of a first process for making fine metallic alloy fibers of the present invention;  
     [0050]FIG. 2 is an isometric view of a metallic alloy wire referred to in FIG. 1;  
     [0051]FIG. 2A is an end view of FIG. 2;  
     [0052]FIG. 3 is an isometric view illustrating a preformed first cladding material referred to in FIG. 1;  
     [0053]FIG. 3A is an end view of FIG. 3;  
     [0054]FIG. 4 is an isometric view illustrating the first cladding material of FIG. 3 encompassing the metallic alloy wire of FIG. 2;  
     [0055]FIG. 4A is an end view of FIG. 4;  
     [0056]FIG. 5 is an isometric view similar to FIG. 4 illustrating the first cladding material being sealed to the metallic alloy wire;  
     [0057]FIG. 5A is an end view of FIG. 5;  
     [0058]FIG. 6 is an isometric view similar to FIG. 5 illustrating the tightening of the first cladding material to the metallic alloy wire in the presence of an inert atmosphere;  
     [0059]FIG. 6A is an end view of FIG. 6;  
     [0060]FIG. 7 is an isometric view similar to FIG. 6 illustrating the first cladding material tightened to the metallic alloy wire;  
     [0061]FIG. 7A is an end view of FIG. 7;  
     [0062]FIG. 8 is an isometric view of the first cladding of FIG. 7 after a first drawing process;  
     [0063]FIG. 8A is an enlarged end view of FIG. 8;  
     [0064]FIG. 9 is an isometric view illustrating an assembly of a multiplicity of the drawn first claddings within a second cladding;  
     [0065]FIG. 9A is an end view of FIG. 9;  
     [0066]FIG. 10 is an isometric view of the second cladding of FIG. 9 after a second drawing process;  
     [0067]FIG. 10A is an enlarged end view of FIG. 10;  
     [0068]FIG. 11 is an isometric view similar to FIG. 10 illustrating the removal of the first and second claddings to provide a multiplicity of fine metallic alloy fibers;  
     [0069]FIG. 11A is an enlarged end view of FIG. 11;  
     [0070]FIG. 12 is a block diagram of a second process for making a fine metallic alloy fiber of the present invention;  
     [0071]FIG. 13 is an isometric view of a metallic alloy wire referred to in FIG. 12;  
     [0072]FIG. 13A is an end view of FIG. 13;  
     [0073]FIG. 14 is an isometric view illustrating a preformed cladding material referred to in FIG. 12;  
     [0074]FIG. 14A is an end view of FIG. 14;  
     [0075]FIG. 15 is an isometric view illustrating the cladding material of FIG. 14 tightened on the metallic alloy wire of FIG. 13;  
     [0076]FIG. 15A is an end view of FIG. 15;  
     [0077]FIG. 16 is an isometric view of the cladding of FIG. 15 after a drawing process;  
     [0078]FIG. 16A is an enlarged end view of FIG. 16;  
     [0079]FIG. 17 is an isometric view similar to FIG. 16 illustrating the removal of the cladding material to provide a fine metallic alloy fiber;  
     [0080]FIG. 17A is an enlarged end view of FIG. 17;  
     [0081]FIG. 18 is a magnified view of FIG. 17A illustrating an enhanced concentration of diffused cladding material at the periphery of the fine metallic alloy fiber;  
     [0082]FIG. 19 is a view similar to FIG. 18 illustrating a homogeneous concentration of the diffused cladding material within the fine metallic alloy fiber;  
     [0083]FIG. 20 is a photograph of the energy dispersive X-ray spectra illustrating the enhanced concentration of diffused cladding material at the periphery of the fine metallic alloy fiber of FIG. 18;  
     [0084]FIG. 21 is a photograph of the energy dispersive X-ray spectra illustrating the homogeneous concentration of the diffused cladding material within the fine metallic alloy fiber of FIG. 19;  
     [0085]FIG. 22 is a block diagram of a third process for making a fine metallic alloy fiber of the present invention;  
     [0086]FIG. 23 is an isometric view of a metallic alloy wire referred to in FIG. 22;  
     [0087]FIG. 23A is an end view of FIG. 23;  
     [0088]FIG. 24 is an isometric view illustrating the forming of a cladding material about the metallic alloy wire referred to in FIG. 22;  
     [0089]FIG. 24A is an end view of FIG. 24;  
     [0090]FIG. 25 is an isometric view illustrating the cladding material of FIG. 24 encompassing the metallic alloy wire of FIG. 23;  
     [0091]FIG. 25A is an end view of FIG. 25;  
     [0092]FIG. 26 is an isometric view of the cladding of FIG. 25 after a drawing process;  
     [0093]FIG. 26A is an enlarged end view of FIG. 26;  
     [0094]FIG. 27 is an isometric view similar to FIG. 26 illustrating the removal of the cladding material to provide a fine metallic alloy fiber;  
     [0095]FIG. 27A is an enlarged end view of FIG. 27;  
     [0096]FIG. 28 is a magnified view of FIG. 27A illustrating an enhanced concentration of diffused cladding material at the periphery of the fine metallic alloy fiber;  
     [0097]FIG. 29 is a view similar to FIG. 28 illustrating a homogeneous concentration of the diffused cladding material within the fine metallic alloy fiber for providing a new alloy;  
     [0098]FIG. 30 is a block diagram of a fourth process for making a fine metallic alloy fiber of the present invention;  
     [0099]FIG. 31 is an isometric view of a metallic alloy wire referred to in FIG. 30;  
     [0100]FIG. 31A is an end view of FIG. 31;  
     [0101]FIG. 32 is an isometric view illustrating an electroplating of a cladding material about the metallic alloy wire referred to in FIG. 31;  
     [0102]FIG. 32A is an end view of FIG. 32;  
     [0103]FIG. 33 is an isometric view of the cladding of FIG. 32 after a drawing process;  
     [0104]FIG. 33A is an enlarged end view of FIG. 33;  
     [0105]FIG. 34 is an isometric view similar to FIG. 33 illustrating the removal of the cladding material to provide a fine metallic alloy fiber;  
     [0106]FIG. 34A is an enlarged end view of FIG. 34; and  
     [0107]FIG. 35 is a magnified view of FIG. 34A illustrating an enhanced concentration of diffused cladding material at the periphery of the fine metallic alloy fiber for providing a fine metallic alloy fiber having surface properties in accordance with the properties of the cladding material.  
    
    
     [0108] Similar reference characters refer to similar parts throughout the several Figures of the drawings.  
     DETAILED DISCUSSION  
     [0109]FIG. 1 is a block diagram illustrating a first embodiment of an improved process  10  for making a fine metallic alloy fiber. In this embodiment of the invention, the improved process  10  is capable of simultaneously making a multiplicity of fine metallic alloy fibers. The first embodiment of the improved process  10  is capable of simultaneously making thousands of individual metallic alloy fibers with each of the fine metallic alloy fibers having a diameter less than 10 micrometers. The improved process  10  of FIG. 1 utilizes a metallic alloy  20  and a cladding material. The metallic alloy  20  is shown being formed from a first alloy component (A) and a second alloy component (B).  
     [0110]FIG. 2 is an isometric view of the metallic alloy wire  20  referred to in FIG. 1 with FIG. 2A being an end view of FIG. 2. The metallic alloy wire  20  extends between a first end  21  and a second end  22 . The metallic alloy wire  20  defines an outer diameter  20 D. The metallic alloy  20  is shown being formed from the first alloy component (A) and the second alloy component (B) to be representative of the two alloy components of a selected two alloy component alloy material. Although the metallic alloy  20  is disclosed as a metallic alloy having two components, it should be appreciated that the metallic alloy  20  may have any number of components as set forth in TABLE I. Preferably, the metallic alloy  20  is in the form of a wire or a similar configuration.  
     [0111] The process  10  of the present invention has been found to work with various types of metallic alloys. In one example of the invention, the metallic alloy wire  20  is selected from the group consisting of Haynes C-22, Haynes C-2000, Haynes HR-120, Haynes HR-160, Haynes 188, Haynes 556, Haynes 214, Haynes 230, Fecralloy Hoskins 875, Fecralloy M, Fecralloy 27-7 and HAST X. The chemical composition of this group of metallic alloys is given in TABLE 1.  
               TABLE I                          CHEMICAL COMPOSITION OF METALLIC ALLOYS                     HAYNES   WEIGHT PERCENT                                                             ALLOYS   Ni   Co   Fe   Cr   Mo   W   Mn   Si   C   La   Others               C-22   56     2.5   3   22   13    3     0.5   0.08   0.01   —   0.035 V       C-2000   59   —   —   23   16    —   —   0.08   0.01   —   1.6 Cu       HR-120   37    3   33    25     2.5   2.5   0.7   0.6    0.05   —   0.7 Cb,0.2 Al       HR-160   37   30     3.5   28     1.0   1.0   0.5   2.75   0.05   —   1.0 Cb       188   22   39   3   22   —   14      1.25   0.35   0.10   0.03       556   20   18   31    22   3   2.5   1     0.4    0.10   0.02   0.6 Ta, 0.2 Al,N       214   75   —   3   16   —   —   0.5   0.2    0.05   —   4.5 Al, 0.01Y       230   57    5   3   22   2   14     0.5   0.4    0.10   0.02   0.3 Al       HAST X   47     1.5   18    22   9   0.6   1     1     0.10   —   0.008B       FECRALLOY   —   —   Bal.     22.5   —   —   —   0.5    0.10   —   5.5 Al, 0.01Y       HOSKINS 875       FECRALLOY   —   —   Bal.   27   2   —   —   —   —   —   7 Al, 0.15 RE       M                  
 
     [0112] Although the process  10  of the present invention has been found useful in forming a fine metallic fiber from a metallic alloy as set forth in TABLE I, it should be understood that the process  10  of the present invention may be used with various other types of metallic alloys.  
     [0113]FIG. 3 is an isometric view illustrating a first cladding material  30  referred to in FIG. 1. The first cladding material  30  extends between a first and a second end  31  and  32 . In this example of the process  10  of the present invention, the first cladding material  30  is shown as a preformed tube  33  having an outer diameter  30 D and an inner diameter  30   d.    
     [0114]FIG. 3A is an enlarged end view of FIG. 3. The inner diameter  30   d  of the preformed tube  33  of the first cladding material  30  is dimensioned to slidably receive the outer diameter  20 D of the metallic alloy wire  20 .  
     [0115] The first cladding material  30  is made of a material which is suitable for use with the selected metallic alloy  20 . The first cladding material  30  may be formed from one of the first alloy component (A) and the second alloy component (B). In this specific example of the invention, the first cladding material  30  is shown as being formed from the first alloy component (A).  
     [0116] In the alternative, the first cladding material  30  is made of other materials which are suitable for use with the selected metallic alloy  20 . In one example of the process  10 , the first cladding material  30  is selected from the group including low carbon steel, copper, pure nickel and Monel  400  alloy. Although the above group of materials has been found useful for the first cladding material  30 , it should be understood that the process  10  of the present invention should not be limited to the specific examples of materials set forth herein.  
     [0117]FIG. 1 illustrates the process step  11  of cladding the metallic alloy wire  20  with the first cladding material  30 . In this example of the invention, the metallic alloy wire  20  is inserted into the preformed tube  33  of the first cladding material  30 .  
     [0118]FIG. 4 is an isometric view similar to FIG. 3 illustrating the first cladding material  30  encompassing the metallic alloy wire  20 . The inner diameter  30   d  of the preformed tube  33  of the first cladding material  30  slidably receives the outer diameter  20 D of the metallic alloy wire  20 . The first end  31  of the first cladding material  30  overlies the first end  21  of the metallic alloy wire  20 .  
     [0119]FIG. 4A is an enlarged end view of FIG. 4. The difference between the inner diameter  30   d  of the preformed tube  33  and the outer diameter  20 D of the metallic alloy wire  20  creates a space  34  therebetween. Preferably, the space  34  is minimized but is sufficient to enable insertion of the metallic alloy wire  20  within the first cladding material  30 .  
     [0120]FIG. 1 illustrates the process step  12  of tightening the first cladding material  30  about the metallic alloy wire  20 . In this example of the invention, the preformed tube  33  of the first cladding material  30  is tightened about the metallic alloy wire  20  in the presence of an inert gas  36 .  
     [0121]FIG. 5 is an isometric view similar to FIG. 4 illustrating the first cladding material  30  being sealed to the metallic alloy wire  20 . Preferably, the preformed tube  33  of the first cladding material  30  is sealed to the metallic alloy wire  20  in the presence of the inert gas  36 .  
     [0122]FIG. 5A is an enlarged end view of FIG. 5. A reducing die  38  seals the first end  31  of the first cladding material  30  to the first end  21  of the metallic alloy wire  20 . More specifically, the reducing die has an inner diameter  38   d  that is smaller than the outer diameter  30 D of the first cladding material  30  and is smaller than the outer diameter  20 D of the metallic alloy wire  20 . The reducing die  38  reduces the first cladding material  30  and the metallic alloy wire  20  therein to have a reduced outer diameter of  30 D′ at the first end  31 .  
     [0123] The insert gas  36  is injected into the space  34  between the inner diameter  30   d  of the pre-formed tube  33  and the outer diameter  20 D of the metallic alloy wire  20  from the second end  32  of the first cladding material  30 . The inert gas  36  purges the space  34  of ambient atmosphere and completely fills the space  34  with the inert gas  36 . In one example of the invention, the inert gas  36  is selected from the group VIIIA of the Periodic table. In many cases, the inert gas  36  is selected from the group VIIIA of the Periodic table on the basis of economy, such as argon, helium or neon.  
     [0124]FIG. 6 is an isometric view similar to FIG. 5 illustrating the tightening of the first cladding material  30  to the metallic alloy wire  20  in the presence of the insert gas  36 . After the space  34  is purged with the inert gas  36 , the remainder of the first cladding material  30  is tightened onto the metallic alloy wire  20  up to the second end  32  of the first cladding material  30 . The inert gas  36  insures that there is no reactive gas is interposed between the metallic alloy wire  20  and the first cladding material  30 .  
     [0125]FIG. 6A is an enlarged end view of FIG. 6. As the first cladding material  30  is tightened against the metallic alloy wire  20  from the first end  31  to the second end  32 , most of the inert gas  36  is squeezed from the space  34  between the metallic alloy wire  20  and the first cladding material  30 . After the first cladding material  30  is tightened against the metallic alloy wire  20 , the combination forms a first cladding  40  having an outer diameter  40 D.  
     [0126]FIG. 7 is an isometric view similar to FIG. 6 illustrating the first cladding material  30  tightened to the metallic alloy wire  20 . The metallic alloy wire  20  has a reduced outer diameter  20 D′ whereas the first cladding material  30  has a reduced outer and inner diameter  30 D′ and  30   d ′, respectively. The first cladding  40  has an outer diameter  40 D.  
     [0127]FIG. 7A is an enlarged end view of FIG. 7. The first cladding material  30  is shown tightened onto the metallic alloy wire  20 . Any minute voids between the between the metallic alloy wire  20  and the first cladding material  30  are filled with the inert gas  36 .  
     [0128]FIG. 1 illustrates the process step  13  of drawing the first cladding  40  for reducing the outer diameter  40 D thereof and for reducing the diameter  20 D′ of the metallic alloy wire  20  within the first cladding  40  to provide a drawn first cladding  45 .  
     [0129]FIG. 8 is an isometric view of the first cladding  40  of FIG. 7 after a first drawing process  13  to provide the drawn first cladding  45 . The drawn first cladding  45  defines an outer diameter  45 D. The outer diameter  20 D of the metallic alloy wire  20  is correspondingly reduced during the first drawing process  13 .  
     [0130]FIG. 8A is an enlarged end view of FIG. 8. Preferably, the first drawing process  13  includes successively drawing the first cladding  40  followed by successive annealing of the first cladding  40 . In the preferred form of the invention, the annealing of the first cladding  40  takes place within a specialized atmosphere such as a reducing atmosphere.  
     [0131] In the best mode of carrying out the invention, the first cladding  40  is rapidly heated within the reducing atmosphere. In one example of the invention, a mixture of hydrogen gas and nitrogen gas is used as the reducing atmosphere during the annealing of the first cladding  40 . The first cladding  40  may be heated rapidly by a conventional furnace or may be heated rapidly by infrared heating or induction heating. The annealing may be accomplished in either a batch process or a continuous process.  
     [0132] Preferably, the annealed first cladding  40  is rapidly cooled within the heat conducting fluid. Tthe first cladding  40  may be cooled rapidly by a quenching annealed first cladding  40  in a high thermoconductive fluid. The high thermoconductive fluid may be a liquid such as water or oil or a high thermoconductive gas such a hydrogen gas. In one example, the thermoconductive gas comprises twenty percent (20%) to one hundred percent (100%) hydrogen. to rapidly cool the first cladding  40 .  
     [0133]FIG. 1 illustrates the process step  14  of assembling a multiplicity of the drawn first claddings  45 . Typically, 400 to 1000 of the drawn first claddings  45  are assembled with the process  10  of the present invention.  
     [0134]FIG. 1 illustrates the process step  15  of cladding the assembly of the multiplicity of the drawn first claddings  45  within a second cladding  50 . The quantity of 400 to 1000 of the drawn first claddings  45  are assembled within the second cladding  50 .  
     [0135]FIG. 9 is an isometric view illustrating the assembly of a multiplicity of the drawn first claddings  45  within the second cladding  50 . The second cladding  50  extends between a first end  51  and a second end  52 .  
     [0136]FIG. 9A is an enlarged end view of FIG. 9. In this example, the second cladding  50  is shown as a preformed tube  53  having an outer diameter  50 D and an inner diameter  50   d . In the alternative, the second cladding  50  may be formed about the assembly of a multiplicity of the drawn first claddings  45 . The second cladding  50  is formed from a second cladding material  60  which is suitable for use with the selected metallic alloy wire  20 . In addition, the second cladding material  60  is made of a material which is suitable for use with the selected first cladding material  30 . In one example, the second cladding material  60  is selected from the group consisting of low carbon steel, copper, pure nickel and Monel  400  alloy. Although the above group of the materials has been found useful for the second cladding material  60 , it should be understood that the process  10  of the present invention may be used with various other types of materials for the second cladding material  60 .  
     [0137]FIG. 1 illustrates the process step  16  of drawing the second cladding  50  for reducing the outer diameter  50 D thereof. The second drawing process  16  reduces the diameter  45 D of the drawn first claddings  45  and the metallic alloy wire  20  within the second cladding  50  to provide a drawn second cladding  65 .  
     [0138]FIG. 10 is an isometric view of the second cladding  50  of FIG. 9 after a second drawing process  16  to provide the drawn second cladding  65 . The drawn second cladding  65  defines an outer diameter  65 D. The outer diameter  20 D of the metallic alloy wire  20  is correspondingly reduced during the second drawing process  16 . The drawing of the second cladding  50  transforms the multiplicity of metallic alloy wires  20  into a multiplicity of fine metallic alloy fibers  70 .  
     [0139]FIG. 10A is an enlarged end view of FIG. 10. Preferably, the second drawing process  16  includes successively drawing the second cladding  50  followed by successive annealing of the second cladding  50 . In the preferred form of the invention, the annealing of the second cladding  50  takes place within a specialized atmosphere such as a reducing atmosphere as set forth above.  
     [0140]FIG. 1 illustrates the process step  17  of removing the first and second cladding materials  30  and  60  from the multiplicity of fine metallic alloy fibers  70 . Preferably, the first and second cladding materials  30  and  60  are removed from the multiplicity of fine metallic alloy fibers  70  by a chemical or an electrochemical process.  
     [0141]FIG. 11 is an isometric view similar to FIG. 10 illustrating the removal of the first and second claddings  30  and  60 . The removal of the first and second claddings  30  and  60  provides a multiplicity of fine metallic alloy fibers  70 . The process step  17  of removing the first and second cladding materials  30  and  60  from the multiplicity of fine metallic alloy fibers  70  may include leaching the first and second drawn claddings  45  and  65  for chemically removing the first and second cladding materials  30  and  60 .  
     [0142]FIG. 11A is an enlarged end view of FIG. 11. The multiplicity of fine metallic alloy fibers  70  may contain thousands of individual metallic alloy fibers  70 . Each of the fine metallic alloy fibers  70  may have a diameter less than 10 micrometers.  
     [0143]FIG. 12 is a block diagram of a second embodiment of an improved process  110  for making a fine metallic alloy fiber of the present invention. The second embodiment of the improved process  110  will be explained with reference to making a single fine metallic alloy fiber. However, it should be understood that the second improved process  110  may be modified to produce a multiplicity of fine metallic alloy fibers in a manner similar to the first process  10  shown in FIGS.  1 - 11 .  
     [0144] The improved process  110  of FIG. 12 utilizes a metallic alloy  120  and a cladding material  130 . The metallic alloy  120  is shown being formed from a first alloy component (A) and a second alloy component (B).  
     [0145]FIG. 13 is an isometric view of the metallic alloy wire  120  referred to in FIG. 12 with FIG. 13A being an end view of FIG. 13. The metallic alloy wire  120  extends between a first end  121  and a second end  122  and defines an outer diameter  120 D. The metallic alloy  20  is shown being formed from the first alloy component (A) and the second alloy component (B) but it should be appreciated that the metallic alloy  120  may have any number of components as set forth in TABLE I.  
     [0146]FIG. 14 is an isometric view illustrating a cladding material  130  referred to in FIG. 12. The cladding material  130  extends between a first and a second end  131  and  132  and is shown as a pre-formed tube  133  having an outer diameter  130 D and an inner diameter  130   d.    
     [0147]FIG. 14A is an enlarged end view of FIG. 14. The inner diameter  130   d  of the preformed tube  133  of the cladding material  130  is dimensioned to slidably receive the outer diameter  120 D of the metallic alloy wire  120  as previously set forth.  
     [0148] The cladding material  130  is made of a material that is compatable with the selected metallic alloy  120 . The cladding material  130  is formed from one of the first alloy component (A) and the second alloy component (B). In this specific example of the invention, the cladding material  130  is shown as being formed from the first alloy component (A).  
     [0149]FIG. 12 illustrates the process step  111  of cladding the metallic alloy wire  120  with the cladding material  130 . The metallic alloy wire  120  is inserted into the preformed tube  133  of the cladding material  130 .  
     [0150]FIG. 15 is an isometric view similar to FIG. 14 illustrating the cladding material  130  encompassing the metallic alloy wire  120 . The inner diameter  130   d  of the preformed tube  133  of the cladding material  130  slidably receives the outer diameter  120 D of the metallic alloy wire  120 . The first end  131  of the cladding material  130  overlies the first end  121  of the metallic alloy wire  120 .  
     [0151]FIG. 15A is an enlarged end view of FIG. 15. Preferably, the cladding material  130  is tightened about the metallic alloy wire  120  in the presence of an inert gas as heretofore described. The cladding material  130  is tightened onto the metallic alloy wire  120  to have a reduced outer diameter of  130 D′. After the cladding material  130  is tightened against the metallic alloy wire  120 , the combination forms a cladding  140  having an outer diameter  140 D.  
     [0152]FIG. 12 illustrates the process step  112  of drawing the cladding  140  for reducing the outer diameter  140 D thereof and for reducing the diameter  120 D′ of the metallic alloy wire  120  within the cladding  140  to provide a drawn cladding  145  having a outer diameter  145 D.  
     [0153]FIG. 12 illustrates the process step  113  of annealing the drawn the cladding  140 . Preferably the drawing process  112  and the annealing process  113  of FIG. 12 are interrelated to include the successive drawing and the successive annealing of the cladding  145 . The time and temperature of the annealing process  113  is established to control the diffusion of the clad material  130  into the metallic alloy wire  120 .  
     [0154] Preferably, the annealing of the cladding  145  takes place within a specialized atmosphere such as a reducing atmosphere. In the best mode of carrying out the invention, the cladding  145  is rapidly heated within the reducing atmosphere to a temperature between 1650° F. and 2050° F.  
     [0155] In one example of the invention, a mixture of hydrogen gas and nitrogen gas is used as the reducing atmosphere during the annealing of the cladding  14 . The cladding  145  may be heated rapidly by a conventional furnace or may be heated rapidly by infrared heating or induction heating.  
     [0156] Preferably, the annealed cladding  145  is rapidly cooled within the heat conducting fluid. The cladding  145  may be cooled rapidly by a quenching annealed cladding  145  in a high thermoconductive fluid. The high thermoconductive fluid may be a liquid such as water or oil or a high thermoconductive gas such a hydrogen gas. In one example, the thermoconductive gas comprises twenty percent (20%) to one hundred percent (100%) hydrogen to rapidly cool the cladding  140 .  
     [0157]FIG. 16 is an isometric view of the cladding  145  of FIG. 15 after the drawing process  112  and the annealing process  113  to provide the drawn cladding  145 . The drawn cladding  145  defines an outer diameter  145 D. The outer diameter  120 D of the metallic alloy wire  120  is correspondingly reduced in the drawing process. The drawing of the cladding  145  transforms the metallic alloy wire  120  into a fine metallic alloy fiber  170 .  
     [0158]FIG. 12 illustrates the process step  114  of removing the cladding material  130  from the fine metallic alloy fiber  170 . Preferably, the cladding material  130  is removed from the fine metallic alloy fiber  170  by a chemical or an electrochemical process.  
     [0159]FIG. 17 is an isometric view similar to FIG. 16 illustrating the removal of the cladding material  130  to provide a fine metallic alloy fiber  170 . The process step  114  of removing the cladding material  130  from the fine metallic alloy fiber  170  may include leaching the drawn cladding  145  for chemically removing the cladding material  130 .  
     [0160]FIG. 17A is an enlarged end view of FIG. 17 illustrating the cross-section of the fine metallic alloy fiber  170 . A portion of the clad material  130  has diffused into the metallic alloy fiber  170  during the annealing process. The diffused clad material  130  provides an enhanced concentration  180  of the clad material  130  at the periphery  190  of the fine metallic alloy fiber  170 .  
     [0161]FIG. 12 illustrates the process step  115  of processing the fine metallic alloy fiber  170 . The fine metallic alloy fiber  170  may be used for a wide variety of intents and purposes. It should be appreciated by those skilled in the art that the present invention should not be limited by the intended use of the fine metallic alloy fiber  170 .  
     [0162] In one example, the fine metallic alloy fiber  170  may be used to make fiber tow for high temperature and/or high corrosive applications. In another example, the fine metallic alloy fiber  170  may be used to make metallic filters as described in U.S. Pat. No. 4,126,566. In a further example, the fine metallic alloy fiber  170  may be used to make metallic membranes. In still a further example, the fine metallic alloy fiber  170  may be used to make catalyst carriers.  
     [0163]FIG. 18 is a magnified view of FIG. 17A illustrating the enhanced concentration  180  of diffused cladding material  130  at the periphery  190  of the fine metallic alloy fiber  170 . During the annealing of the cladding  140 , a portion of the cladding material  130  has migrated or diffused into the periphery  190  of the fine metallic alloy fiber  170 .  
     [0164] A portion of the first alloy component (A) of the cladding material  130  has migrated or diffused into the periphery  190  of the fine metallic alloy fiber  170 . The migration or diffusion of the first alloy component (A) of the cladding material  130  results in an excess of the first alloy component (A) relative to the amounts of the first alloy component (A) and the second alloy component (B) in a central region  195  of the fine metallic alloy fiber  170 .  
     [0165]FIG. 12 illustrates the process step  116  of heating the fine metallic alloy fiber  170 . The process step  116  of heating the fine metallic alloy fiber  170  may be undertaken simultaneously with the process step  115  of processing the fine metallic alloy fiber  170 . For example, the process step  116  of heating the fine metallic alloy fiber  170  may be undertaken simultaneously with the sintering of a matrix of the fine metallic alloy fibers  170 . In the alternative, the process step  116  of heating the fine metallic alloy fiber  170  may be undertaken independently of the process step  115  of processing the fine metallic alloy fiber  170 .  
     [0166] The fine metallic alloy fiber  170  are heated to a temperature sufficient to further diffuse the minimally diffused cladding material  130  into the metallic alloy fiber  170  to provide a substantially homogeneous fine metallic alloy fiber  170 . The excess of the first alloy component (A) of the cladding material  130  at the periphery  190  of the fine metallic alloy fiber  170  further migrates or diffuses into the central region  195  of the fine metallic alloy fiber  170 . The further migration or diffusion of the excess of the first alloy component (A) from the periphery  190  into the central region  195  of the fine metallic alloy fiber  170  results in a substantially uniform concentration of the first alloy component (A) and the second alloy component (B) throughout the fine metallic alloy fiber  170 .  
     [0167] Preferably, the fine metallic alloy fiber  170  is heated to a temperature above 2100° F. The fine metallic alloy fiber  170  is heated at the temperature above 2100° F. for a period of time sufficient to further diffuse the diffused cladding material  140  into the metallic alloy fiber  170  to provide a substantially homogeneous fine metallic alloy fiber  170 .  
     [0168]FIG. 19 is a view similar to FIG. 18 illustrating a homogeneous concentration of the first alloy component (A) and the second alloy component ( 13 ) throughout the fine metallic alloy fiber  170 . The excess of the first alloy component (A) from the periphery  190  has migrated into the central region  195  of the fine metallic alloy fiber  170  to provide a substantially homogeneous fine metallic alloy fiber  170 .  
     [0169]FIG. 20 is a photograph of the energy dispersive X-ray spectra illustrating the enhanced concentration  180  of diffused cladding material  130  at the periphery  190  of the fine metallic alloy fiber  170  of FIG. 18. The dots in the photograph indicated the concentration of the first alloy component (A) at the periphery  190  of the fine metallic alloy fiber  170 .  
     [0170]FIG. 21 is a photograph of the energy dispersive X-ray spectra illustrating the homogeneous concentration of the diffused cladding material  130  within the fine metallic alloy fiber of FIG. 19. The dots in the photograph indicate the uniform concentration of the first alloy component (A) throughout the fine metallic alloy fiber  170 .  
     [0171]FIG. 22 is a block diagram of a third embodiment of an improved process  210  for making a fine metallic alloy fiber of the present invention. The third embodiment of the improved process  210  will be explained with reference to making a single metallic alloy fiber. It should be understood that the third process  210  may be modified to produce a multiplicity of fine metallic alloy fibers in a manner similar to the first process  10  shown in FIGS.  1 - 11 .  
     [0172] The improved process  210  of FIG. 22 utilizes a metallic alloy  220  and a cladding material  230 . The metallic alloy  220  is shown being formed from a first alloy component (A) and a second alloy component (B).  
     [0173]FIG. 23 is an isometric view of the metallic alloy wire  220  referred to in FIG. 22 with FIG. 23A being an end view of FIG. 23. The metallic alloy wire  220  extends between a first end  221  and a second end  222  and defines an outer diameter  220 D. The metallic alloy  220  is shown being formed from the first alloy component (A) and the second alloy component (B).  
     [0174]FIG. 22 illustrates the process step  211  of cladding the metallic alloy wire  220  with the cladding material  230 . The cladding material  230  is formed about the metallic alloy wire  220 .  
     [0175]FIG. 24 is an isometric view illustrating a cladding material  230  referred to in FIG. 22. The cladding material  230  is shown being formed about the outer diameter  220 D of the metallic alloy wire  220 .  
     [0176]FIG. 24A is an enlarged end view of FIG. 24. The inner diameter  230   d  of the cladding material  230  is bent against the outer diameter  220 D of the metallic alloy wire  220  to provide intimate contact between the cladding material  230  the outer diameter  220 D of the metallic alloy wire  220 .  
     [0177] The cladding material  230  is made of a material that is compatible with the selected metallic alloy  220 . The cladding material  230  is formed from a third alloy component (C). The third alloy component (C) is different from the first alloy component (A) and the second alloy component (B).  
     [0178]FIG. 25 is an isometric view similar to FIG. 24 illustrating the cladding material  230  encompassing the metallic alloy wire  220  with FIG. 25A being an enlarged end view of FIG. 25. The cladding material  230  is tightened about the metallic alloy wire  220  in the presence of an inert gas. The cladding material  230  is tightened onto the metallic alloy wire  220  to have a reduced outer diameter of  230 D′ to form a cladding  240  having an outer diameter  240 D.  
     [0179]FIG. 22 illustrates the process step  212  of drawing the cladding  240  for reducing the outer diameter  240 D thereof and for reducing the diameter  220 D′ of the metallic alloy wire  220  within the cladding  240  to provide a drawn cladding  245  having a outer diameter  245 D.  
     [0180]FIG. 22 illustrates the process step  213  of annealing the drawn cladding  245 . Preferably the drawing process  212  and the annealing process  213  of FIG. 22 are interrelated to include the successive drawing and the successive annealing of the cladding  245 . The time and temperature of the annealing process  213  is established to control the diffusion of the clad material  230  into the metallic alloy wire  220 . Preferably, the annealing of the cladding  240  takes place within a specialized atmosphere such as a reducing atmosphere as set forth previously  
     [0181]FIG. 26 is an isometric view of the drawn cladding  245  of FIG. 25 after the drawing process  212  and the annealing process  213  to provide the drawn cladding  245 . The drawn cladding  245  defines the outer diameter  245 D. The outer diameter  220 D of the metallic alloy wire  220  is correspondingly reduced in the drawing process. The drawing of the cladding  240  transforms the metallic alloy wire  220  into a fine metallic alloy fiber  270 .  
     [0182]FIG. 22 illustrates the process step  214  of removing the cladding material  230  from the fine metallic alloy fiber  270 . Preferably, the cladding material  230  is removed from the fine metallic alloy fiber  270  by a chemical or an electrochemical process.  
     [0183]FIG. 27 is an isometric view similar to FIG. 26 illustrating the removal of the cladding material  230  to provide a fine metallic alloy fiber  270 . The process step  214  of removing the cladding material  230  from the fine metallic alloy fiber  270  may include leaching the drawn cladding  245  for chemically removing the cladding material  230 .  
     [0184]FIG. 27A is an enlarged end view of FIG. 27 illustrating the cross-section of the fine metallic alloy fiber  270 . A portion of the clad material  230  has diffused into the metallic alloy fiber  270  during the annealing process  213 . A concentration  280  of the diffused cladding material  230  is located at the periphery  290  of the fine metallic alloy fiber  270 .  
     [0185]FIG. 28 is a magnified view of FIG. 27A illustrating the concentration  280  of diffused cladding material  230  at the periphery  290  of the fine metallic alloy fiber  270 . During the annealing of the cladding  245 , a portion of the cladding material  230  has migrated or diffused into the periphery  290  of the fine metallic alloy fiber  270 .  
     [0186] A portion of the third alloy component (C) of the cladding material  230  has migrated or diffused into the periphery  290  of the fine metallic alloy fiber  270 . The third alloy component (C) is different from the first alloy component (A) and the second alloy component (B) in a central region  295  of the fine metallic alloy fiber  270 .  
     [0187]FIG. 22 illustrates the process step  215  of heating the fine metallic alloy fiber  270 . The fine metallic alloy fiber  270  is heated to a temperature sufficient to further diffuse the diffused cladding material  230  into the metallic alloy fiber  270  to provide a fine metallic alloy fiber  270  formed from a new alloy. The new alloy is formed from the first alloy component (A) and the second alloy component (B) of the fine metallic alloy fiber  270  and the third alloy component (C) of the cladding material  230 . Preferably, the fine metallic alloy fiber  270  is heated to a temperature above 2100° F. The fine metallic alloy fiber  270  may be heated at the temperature above 2100° F. for a period of time sufficient to diffuse the third alloy component (C) throughout the first alloy component (A) and the second alloy component (B). In the alternative, the fine metallic alloy fiber  270  may be heated at the temperature above 2100° F. for a period of time sufficient to only partially diffuse the third alloy component (C) into the first alloy component (A) and the second alloy component (B)  
     [0188]FIG. 29 is a view similar to FIG. 28 illustrating the new alloy formed from the first alloy component (A), the second alloy component (B) and the third alloy component (C). The third alloy component (C) has been totally and uniformly diffused throughout the first alloy component (A) and the second alloy component (B).  
     [0189]FIG. 30 is a block diagram of a fourth embodiment of an improved process  310  for making a fine metallic alloy fiber of the present invention. The third embodiment of the improved process  310  will be explained with reference to making a single metallic alloy fiber. It should be understood that the third process  310  may be modified to produce a multiplicity of fine metallic alloy fibers in a manner similar to the first process  10  shown in FIGS.  1 - 11 .  
     [0190] The improved process  310  of FIG. 30 utilizes a metallic alloy  320  and a cladding material  330 . The metallic alloy  320  is shown being formed from a first alloy component (A) and a second alloy component (B).  
     [0191]FIG. 31 is an isometric view of the metallic alloy wire  320  referred to in FIG. 30 with FIG. 31A being an end view of FIG. 31. The metallic alloy wire  320  extends between a first end  321  and a second end  322  and defines an outer diameter  320 D. The metallic alloy  320  is shown being formed from the first alloy component (A) and the second alloy component (B).  
     [0192]FIG. 30 illustrates the process step  311  of cladding the metallic alloy wire  320  with the cladding material  330 . The cladding material  230  is electroplated onto the metallic alloy wire  320 .  
     [0193]FIG. 32 is an isometric view illustrating a cladding material  330  referred to in FIG. 30. The cladding material  330  is shown electoplated on the outer diameter  320 D of the metallic alloy wire  320 .  
     [0194]FIG. 32A is an enlarged end view of FIG. 32. The inner diameter  330   d  of the cladding material  230  provides intimate contact with the outer diameter  320 D of the metallic alloy wire  320 . The cladding material  330  is made of a material that is compatible with the selected metallic alloy  320 . The cladding material  340  is formed from a fourth component (D). The fourth component (D) is different from the first alloy component (A) and the second alloy component (B). The fourth component (D) may be an alloy material or a non-alloy material.  
     [0195]FIG. 30 illustrates the process step  312  of drawing the cladding  340  for reducing the outer diameter  340 D thereof and for reducing the diameter  320 D of the metallic alloy wire  220  within the cladding  240  to provide a drawn cladding  245  having a outer diameter  245 D.  
     [0196]FIG. 30 illustrates the process step  313  of annealing the drawn cladding  345 . Preferably the drawing process  312  and the annealing process  313  of FIG. 30 are interrelated to include the successive drawing and the successive annealing of the cladding  345 . The time and temperature of the annealing process  313  is established to control the diffusion of the clad material  3330  into the metallic alloy wire  320 . Preferably, the annealing of the cladding  340  takes place within a specialized atmosphere such as a reducing atmosphere as set forth previously.  
     [0197]FIG. 33 is an isometric view of the drawn cladding  345  of FIG. 30 after the drawing process  312  and the annealing process  313  to provide the drawn cladding  345 . The drawn cladding  345  defines the outer diameter  345 D. The drawing of the cladding  345  transforms the metallic alloy wire  320  into a fine metallic alloy fiber  370 .  
     [0198]FIG. 30 illustrates the process step  314  of removing the cladding material  330  from the fine metallic alloy fiber  370 . Preferably, the cladding material  330  is removed from the fine metallic alloy fiber  370  by a chemical or an electrochemical process.  
     [0199]FIG. 34 is an isometric view similar to FIG. 33 illustrating the removal of the cladding material  330  to provide a fine metallic alloy fiber  370 .  
     [0200]FIG. 34A is an enlarged end view of FIG. 34 illustrating the cross-section of the fine metallic alloy fiber  370 . A portion of the clad material  330  has diffused into the metallic alloy fiber  370  during the annealing process  213 . A concentrated  380  of the diffused cladding material  330  is located at the periphery  390  of the fine metallic alloy fiber  370 .  
     [0201]FIG. 35 is a magnified view of FIG. 34A illustrating the concentration  380  of diffused cladding material  330  at the periphery  390  of the fine metallic alloy fiber  370 . During the annealing of the cladding  345 , a portion of the cladding material  330  has migrated or diffused into the periphery  390  of the fine metallic alloy fiber  370 .  
     [0202] A portion of the fourth component (D) of the cladding material  330  has migrated or diffused into the periphery  390  of the fine metallic alloy fiber  370 . The fourth component (D) is different from the first alloy component (A) and the second alloy component (B) in a central region  295  of the fine metallic alloy fiber  370 .  
     [0203] The fourth component (D) located on the periphery  390  of the fine metallic alloy fiber  370  providing a fine metallic alloy fiber  370  having surface properties in accordance with the properties of the cladding material  330 . The surface properties of the fine metallic alloy fiber  370  is in accordance with the properties of the fourth component (D).  
     [0204] The following Examples I-V set forth specific parameters for the processes of the present invention. It should be appreciated by those skilled in the art that the EXAMPLES I-V may be modified for providing other processes and should not be construed to be limiting upon the present invention.  
     EXAMPLE I  
     [0205]                               ANNEALING CLADDING                                        OBJECT:   General annealing of alloy fiber to preserve original           composition       PROCESS:   Temperature 0.8 of melting point of alloy to be annealed           Time of surface diffusion during annealing measured in           seconds to minutes       RESULT:   Alloy fiber annealed with minimal diffusion of cladding           into the ally fibers                    
     EXAMPLE II  
     [0206]                               DIFFUSION                                        OBJECT:   General sintering of alloy fibers to diffuse to diffuse           cladding into alloy fibers       PROCESS:   Temperature 0.90 to 0.95 of melting point of alloy           Time of volume diffusion during sintering measured in           hours       RESULT:   Cladding material fully diffused                    
     EXAMPLE III  
     [0207]                               ADVANCED ALLOY HAYNES C-2000                                        OBJECT:   To make a final composition: 59%Ni; 23%Cr; 16%Mo;           1.6%Cu.       PROCESS:   Metallic alloy wire having a composition           59%Ni—23%Cr—16%Mo (with no copper) is clad with a           copper cladding material to form a cladding. The           cladding is drawn using intermediate annealing. An           excess of copper clad material is diffused on the           peripheral surface of the fiber. After a heating process           the copper diffuses into the central region of the fiber.       RESULT:   The final composition is Ni—Cr—Mo—Cu.                    
     EXAMPLE IV  
     [0208]                               ADVANCED SURFACE LAYER                                        OBJECT:   To make a surface layer with properties different from the           composition of the fiber       PROCESS:   Nickel rod is plated or cladded with a copper cladding           material. A thin diffusion layer of nickel-copper           alloy is formed during the drawings and annealing process.       RESULT:   The alloy is designed to match the composition of Monel           type alloy (Monel 400 for example) to withstand the           exposure to fluorine/fluoride-bearing reducing           environment.                    
     EXAMPLE V  
     [0209]                               ADVANCED SURFACE LAYER                                        OBJECT:   To make a fiber with a surface layer of precious metal for           catalytic processes or jewelry applications       PROCESS:   Low cost metal is plated by precious metal such as platinum           A thin diffusion layer of platinum alloy is formed           during the drawings and annealing process.       RESULT:   Precious metal layer on low cost substrate                    
     [0210] The present invention provides fine fiber made from a metallic alloy and a new process for forming the fiber from a metallic alloy. The process is capable of forming fiber from a metallic alloy wherein the fine metallic alloy fiber has a diameter less than ten microns. The process is capable of forming high quality fine metallic alloy fibers at an economical cost in commercial quantities.  
     [0211] The present disclosure includes that contained in the appended claims as well as that of the foregoing description. Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and scope of the invention.