Patent Publication Number: US-2003222120-A1

Title: Devices for and methods of casting and bonding a molten material onto one or more surfaces of a moving substrate

Description:
FIELD OF INVENTION  
       [0001] The present invention relates to devices for and methods of continuous forming a profile, e.g., a metallic profile, on a moving substrate. More particularly, the present invention relates to devices for and methods of continuously casting a molten material, e.g., solder, onto at least one surface of a moving substrate, e.g., a base metal substrate, to provide a profile, and a casting die therefor.  
       DESCRIPTION OF THE RELATED ART  
       [0002] Methods of joining materials, e.g., metals, that are of different composition and/or exhibit different material properties, e.g., melting point, include, inter alia, soldering, welding, coating, cladding, and casting. Soldering comprises a method of making a connection, or bond, between a solder and a base metal having a higher melting point than the solder. In the soldering process, the solder and base metal are heated to a temperature at which the solder chemically reacts with the base metal to form a bond.  
       [0003] Welding involves joining two dissimilar metals through the creation of a molten weld puddle, which is comprised of both parent metals. In welding, neither component is totally consumed and, furthermore, both parent metals remain solid and in their original geometry except at the common molten weld zone.  
       [0004] As its name suggests, “coating” involves applying a relatively thin layer of metal, e.g., lead, to a base metal, e.g., steel, and allowing the applied metal, i.e., the “coating”, to cool to form a new layer on the base metal. Coating can be applied through molten dipping, thermal spraying, vapor depositing or sputtering techniques. Application rate of the coating and duration of the technique determines the coating thickness.  
       [0005] Cladding involves joining metals and/or alloys using force or pressure. Bonding between clad layers depends on atomic attraction or diffusion between dissimilar metals brought into intimate contact.  
       [0006] Casting technology has developed from historical static casting techniques in which molten metal is poured into a stationary block mold. Developments over the past half-century have seen commercialization of continuous casting technology. With casting, molten metal is continuously fed into an open, e.g., four-sided or round die to produce long castings of a given cross-section. Continuous casting methods to date, however, involve only one alloy or metal.  
       [0007] For more than thirty years, the metals industry has produced electronic components and other devices comprising a strip of metal bonded to a wider base metal according to the teachings of Spooner, et al. in British Patent No. 1,162,887; hereinafter “the Spooner Patent”. The Spooner patent addresses the inherent problems associated with applying a solder stripe to a substrate. A non-exhaustive list of the problems includes controlling the width, thickness, and location of the molten solder profile. Moreover, the Spooner patent purportedly addresses problems that occur while the substrate is moving at high speeds. The Spooner patent teaches a method of continuously bonding a narrow, preformed strip of solder onto a wider base metal strip, which method generally comprises the steps of:  
       [0008] continuously pulling the base metal substrate and the solder strip towards each other;  
       [0009] wipe-wetting all or a portion of the base metal substrate in a longitudinal direction with flux;  
       [0010] superposing the solder strip onto the base metal substrate at the desired location;  
       [0011] compressing the solder strip onto the base metal substrate;  
       [0012] heating the joined solder strip and base metal substrate; and  
       [0013] cooling the joined solder strip and base metal substrate.  
       [0014] Problems inherent to the Spooner process, however, include the lack of control over the molten solder profile during the heating step, which, as a result, requires further post-cooling machining to reduce the rough solder profile to the desired solder profile. This additional machining requires special equipment, additional equipment operators, and time to perform, which equate to greater expense. Furthermore, solder that is removed during the machining process is wasted, which is another unnecessary expense. Finally, the process described in the Spooner patent can only be used to provide a solder profile on one surface of the metal substrate. Thus, Spooner does not teach or disclose a method for providing solder profiles on both surfaces of the metal substrate.  
       BACKGROUND OF THE INVENTION  
       [0015] In this setting, it would be desirable to provide devices for and methods of continuously casting and bonding at least one, e.g., metal, profile onto a wider moving substrate that minimize post-solidification machining requirements and the amount of waste solder. Such a method solidifies a defined cross-section of a molten material, e.g., metal casting onto a moving substrate further utilizing the moving substrate itself as one of the containing sides of the casting die. Such devices and methods, necessarily, require that the molten material be cast onto a heated, moving substrate through at least one casting die, and preferably through two dies that are disposed on the upper and lower surfaces of the heated substrate, and subsequently cooled.  
       [0016] More particularly, it also would be desirable to provide devices for and methods of continuously casting and bonding at least one metal profile of a defined cross-section onto a moving base metal substrate. Such devices and methods, necessarily, require that the molten material, e.g., solder, be cast onto a heated, moving substrate through at least one casting die, and preferably two dies that are disposed on the upper and lower surfaces of the heated, moving substrate, and subsequently cooled to solidify.  
       SUMMARY OF THE INVENTION  
       [0017] In general, the present invention includes methods of and devices for continuously casting molten material, e.g., solder, onto one or more surfaces of a moving substrate, e.g., a metal strip, to provide one or more profiles on one or more surfaces are disclosed in the present invention. In general, the casting method includes providing a substrate, a heated reservoir of a molten material, and a casting die; moving the substrate past the casting die into which the molten material is introduced; containing the molten material in a casting channel in the casting die against the one or more surfaces of the moving substrate; heating the casting die to prevent the molten material from solidifying against the casting surface prematurely; and cooling the molten material to solidify the molten material to provide one or more profiles on one or more surfaces of the moving substrate and to bond the solidified profile(s) to the one or more surfaces. In general, the device for casting and bonding a molten material to one or more surfaces of a moving substrate includes a casting die for wetting the moving substrate with the molten material to provide one or more desired profiles on one or more surfaces of the moving substrate; a heating system to prevent molten material from solidifying in the casting die; and a cooling device for solidify the molten material in the desired profile(s) and for bonding the desired profile(s) to the one or more surfaces of the moving substrate.  
       [0018] One embodiment of the present invention provides a method of casting molten material one or more surfaces of a moving substrate to provide one or more profiles on at the one or more surfaces, the method comprising the steps:  
       [0019] providing a moving substrate;  
       [0020] providing a casting device that includes a casting die and a cooling device;  
       [0021] providing a reservoir of molten material and a conduit to communicate the molten material to the casting die;  
       [0022] moving the substrate past the casting die,  
       [0023] containing and shaping the molten material into a profile against one or more surfaces of the moving substrate;  
       [0024] heating the casting channel to prevent molten material from solidifying against the channel surfaces, thereby allowing the molten material to fill the casting channel completely; and  
       [0025] cooling the molten material in a cooling device to solidify the molten material to provide one or more profiles on one or more surfaces of the moving substrate to retain the shape of the casting channel when exiting and to bond the profile(s) to the moving substrate.  
       [0026] Optionally, the method can include pre-heating the moving substrate prior to moving the substrate past the casting die; and applying flux to at least one surface of the moving substrate prior to moving the substrate past said casting die.  
       [0027] Modifications and variations of this first embodiment can include casting the molten material to the upper and lower surfaces of the moving substrate while the apparatus is substantially parallel or substantially orthogonal to the direction of movement of the moving substrate.  
       [0028] In a second embodiment, the present invention includes an apparatus for casting and bonding a molten material onto one or more surfaces of a moving substrate to provide one or more profiles those surfaces, wherein the apparatus comprises:  
       [0029] a casting device;  
       [0030] a decoiling device from which the moving substrate is drawn; and  
       [0031] a coiling device onto which the moving substrate, having one or more profiles is collected, wherein the casting device comprises:  
       [0032] a heated reservoir for containing molten material;  
       [0033] a casting die, having upstream and downstream portions and at least one casting channel that is disposed between the upstream portion and the downstream portion, past which the moving substrate is capable of being moved, wherein the casting channel(s) faces the surface(s) of the moving substrate and contains and shapes the molten material into a profile(s) against those surfaces;  
       [0034] a heating system for heating the upstream portion and casting channel of the casting die to prevent the molten material from solidifying within the casting channel, thereby allowing the molten material to fill the casting channel completely; and  
       [0035] a cooling device for solidifying the molten material to provide one or more profiles against said one or more surfaces of the moving substrate and for bonding the profile(s) to those surfaces.  
       [0036] An apparatus in accordance with the present embodiment also can comprise a pre-heating device to heat the moving substrate prior to the substrate entering the casting device to remove contaminants and to improve bonding; and a fluxing device that applies a flux to the moving substrate to remove contaminants.  
       [0037] Modifications and variations of this second embodiment can include casting the molten material to the upper and lower surfaces of the moving substrate while the casting is substantially parallel or substantially orthogonal to the direction of movement of the moving substrate. Moreover, when the apparatus provides one or more profiles on the upper and lower surface, the apparatus further comprises a plurality of equalization channels that allow molten material to communicate with a first casting device that is disposed to face the upper surface of the moving substrate and a second casting device that is disposed to face the lower surface of the moving substrate.  
       [0038] In a third embodiment, the present invention teaches a casting device for casting molten material to provide a profile(s) on one or more surfaces of a moving substrate. Accordingly, the casting device comprising:  
       [0039] a heated reservoir for containing molten material;  
       [0040] a casting die, having upstream and downstream portions and at least one casting channel that is disposed between the upstream portion and the downstream portion, past which the moving substrate is capable of being moved, wherein said at least one casting channel faces said at least one upper surface and lower surface of said moving substrate and contains and shapes the molten material into one or more profiles against at least one of said upper surface and said lower surface of the moving substrate;  
       [0041] a heating system for heating the upstream portion and casting channel of the casting die to prevent the molten material from solidifying within the casting channel, thereby allowing the molten material to fill the casting channel completely; and  
       [0042] a cooling device for solidifying the molten material to provide a profile(s) on a surface(s) of the moving substrate and for bonding the profile(s) to the surface(s) of the moving substrate.  
       [0043] Preferably, this embodiment of the present invention comprises an upper die portion that is removably attachable to a lower die portion, wherein at least one of the upper die portion and the lower die portion includes a casting channel having casting surfaces for containing and shaping the molten material into a profile against at least one surface of the moving substrate. More preferably, the upper mold is a reverse mirror image of the lower mold.  
       [0044] In a fourth embodiment, the present invention teaches a die for casting molten material to provide one or more profiles on a single surface of a moving substrate. More specifically, the die comprises:  
       [0045] an upper die portion having a casting channel further having casting surfaces for containing and shaping the molten material into one or more profiles against a single surface of the moving substrate;  
       [0046] a lower die portion that is releasably attachable to the upper die portion; and  
       [0047] an inlet for communicating molten material from a heated reservoir to the casting channel of the upper die portion.  
       [0048] Alternatively, the die further can comprise a plurality of heating elements for heating the die to prevent molten material from solidifying within the casting channel to allow the molten material to fill the casting channel completely; a solidification region having cooling means that is disposed downstream of the casting channel for solidifying the molten material to provide one or more profiles and bonding said one or more profiles to the upper surface of the moving substrate; and/or a temperature isolation barrier that is disposed between the casting channel and the solidification region.  
       [0049] In a fifth embodiment, the present invention teaches a die for casting molten material to provide one or more profiles on an upper surface one or more profiles on a lower surface of a moving substrate. More specifically, the die comprises:  
       [0050] an upper die portion having a first casting channel further having casting surfaces for containing and shaping the molten material into one or more profiles against the upper surface of the moving substrate;  
       [0051] a lower die portion having a second casting channel further having casting surfaces for containing and shaping the molten material into one or more profiles against the lower surface of the moving substrate, wherein the lower die portion is releasably attachable to the upper die portion; and  
       [0052] an inlet for communicating molten material from a heated reservoir to the casting channels.  
       [0053] Optionally, the die, further, can include a plurality of equalization channels that are structured and arranged between the first casting channel and the second casting channel to allow molten material to communicate between the first casting channel and the second casting channel.  
       [0054] Alternatively, the die further can comprise a plurality of heating elements for heating the die to prevent molten material from solidifying within the first and second casting channels to allow the molten material to fill the first and second casting channels completely; a solidification region having cooling means that is disposed downstream of the first and second casting channels for solidifying the one or more profiles and bonding said one or more profiles to the upper and lower surfaces of the moving substrate; and/or a temperature isolation barrier that is disposed between the casting channels and the solidification region. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWING  
     [0055] For a fuller understanding of the nature and desired objects of the present invention, reference is made to the following detailed description taken in conjunction with the accompanying drawing figures wherein like reference characters denote corresponding parts throughout the several views and wherein:  
     [0056]FIG. 1 shows an illustrative embodiment of an apparatus for casting and bonding a molten material to one or more surfaces of a substantially horizontally moving substrate;  
     [0057]FIG. 2 shows an illustrative embodiment of an apparatus for casting and bonding a molten material to one or more surfaces of a substantially vertically moving substrate;  
     [0058]FIG. 3A shows a side, cut-away view of an embodiment of a single-sided casting device for casting a molten material to provide a profile on a single surface of a moving substrate;  
     [0059]FIG. 3B shows a cross-sectional view of an embodiment of the strip sealing section of a single-sided casting device;  
     [0060]FIG. 3C shows a cross-sectional view of an embodiment of the reservoir and transition zone of a single-sided casting device;  
     [0061]FIG. 3D shows a cross-sectional view of an embodiment of the solidification region of a single-sided casting device;  
     [0062]FIG. 4A shows a side, cut-away view of an embodiment of preheating means and fluxing means;  
     [0063]FIG. 4B shows a top view of an embodiment of preheating means and fluxing means;  
     [0064]FIG. 5 shows a cross-sectional view of another embodiment of the solidification region of a single-sided casting device;  
     [0065]FIG. 6A shows a side, cut-away view of an embodiment of a double-sided casting device for casting a molten material to provide a profile on an upper surface and a lower surface of a moving substrate;  
     [0066]FIG. 6B shows a cross-sectional view of an embodiment of the strip sealing section of a double-sided casting device;  
     [0067]FIG. 6C shows a cross-sectional view of an embodiment of the reservoir and transition zone of a double-sided casting device;  
     [0068]FIG. 6D shows a cross-sectional view of an embodiment of the solidification region of a double-sided casting device;  
    
    
     DETAILED DESCRIPTION OF THE INVENTION AND THE PREFERRED EMBODIMENTS THEREOF  
     [0069] Referring now to the various figures, there is shown in FIG. 1 a first embodiment of an apparatus  10  for casting and bonding a molten material  15  onto a substantially horizontally moving substrate  19  to provide a profile  35 , wherein the profile that is less wide than the lateral dimension of the moving substrate  19 . Preferably, the molten material  15  comprises a molten metal or metal alloy and the moving substrate  19  comprises a strip of a base metal. More preferably, the molten material  15  is a lead-tin solder that can include trace amounts of, e.g., silver, indium, bismuth, antimony, and/or copper, and the moving substrate can include strips of copper, copper alloys, and/or ferrous metals. Alternatively, the molten material  15  can be lead and or indium.  
     [0070] Those skilled in the art will appreciate that changes and variations can be made to the apparatus  10  without departing from the spirit or scope of this disclosure. Indeed, the invention can be practiced using other than metal molten material  15 . For example, the molten material  15  can include glass, rubber, polymers, plastics, carbonaceous products and the like and the moving substrate  19  can include porous materials, e.g., a mesh, screen, fibers, and the like.  
     [0071] In a preferred embodiment, the apparatus  10  comprises a take-up coiler device  12 , a pay-off decoiler device  14 , a preheating device  16 , and a casting device  18 . Optionally, one or more idle coilers  13  can be disposed, e.g., between the pay-off decoiler device  14  and the preheating device  16  and/or between the take-up coiler device  12  and the casting device  18 , to guide and provide intermediate support to the moving substrate  19 . Optionally, the apparatus  10  also can be structured and arranged to include a fluxing device  17 .  
     [0072] A preferred method of casting and bonding a molten material  15  onto a moving substrate  19  to provide at least one profile  35  thereon will now be described to better describe the function of and interplay between the elements of the apparatus  10 . In a preferred embodiment, the moving substrate  19 , hereinafter the “metal strip  19 ”, is structured and arranged, e.g., in an unwindable, rotatable coil  55  of a type that is well known to the art. The unwindable, rotatable coil  55  can include a central hub  56  of sufficient dimension to pass over a supporting bar or axle  58 . If the bar or axle  58  is fixedly attached to the apparatus  10  or to a separate support structure so as not to rotate, then there should be sufficient clearance between the outer diameter of the bar or axle  58  and the inner diameter of the hub  56  to allow the coil  55  to rotate freely about the bar or axle  58  when a pulling force is applied to the free, running end of the metal strip  19 . Alternatively, if the bar or axle  58  is rotatable and/or driven by a motor, then the dimensions of the central hub  56  of the coil  55  provide an interference fit with the bar or axle  58 .  
     [0073] Preferably, the coil  55  is disposed on the pay-off decoiler device  14 . The pay-off decoiler device  14  can comprise, e.g., a cylindrical, substantially horizontal bar or axle  58  that is fixedly attached to the apparatus  10  at one end thereof, i.e., at the decoiling end, or to a separate support structure (not shown) so as not to rotate. Alternatively, the bar or axle  58  is rotatably attached to the apparatus  10 , e.g., at the decoiling end, or to a separate support structure. According to this alternative arrangement, the bar or axle  58  can rotate about an axis. Preferably, a drive motor (not shown) that is capable of providing any desirable rate of rotation can rotate the bar or axle  58  to facilitate the decoiling, or unwinding, process.  
     [0074] The metal strip  19  that is wound on the coil  55  can be unwound by applying a pulling force to the free, running end of the coil  55 . After the metal strip  19  leaves the coil  55 , the metal strip  19  can enter a preheating device  16  where it can be heated to a temperature that is about 20 to about 100 degrees Fahrenheit (° F.) above the liquidus temperature of the molten material  15 . The purpose of preheating the metal strip  19  is twofold. First, the heat removes some of the contaminants on the surfaces of the metal strip  19 . Secondly, a heated metal strip  19  provides enhanced adherence, i.e., bonding, of molten material  15  than a cooler metal strip  19  provides.  
     [0075] Preheating is provided through one or a combination of the following means, depending on the alloy system and its heating requirements. Heating requirements are determined relative to the liquidus of the cast metal, the heat capacity, thermal conductivity of the metal strip  19  run rates, and oxidation considerations. Referring to FIG. 4A, preferably, when molten material  15  is applied to a metal strip  19  that is structured and arranged in a substantially horizontal orientation, preheating is accomplished by conduction using heated, highly-conductive, e.g., copper or graphite, blocks  40   a  and  40   b  that thermally communicate with the metal strip  19  for the purpose of heating the metal strip  19  before the metal strip  19  enters the casting device  18 . Heating blocks  40   a  and  40   b  can be disposed to communicate heat by conduction to the upper surface  34  of the metal strip  19  and the lower surface  38  of the metal strip  19 , respectively. Alternatively, just the upper heating block  40   a  can be disposed to communicate thermally with so to heat upper surface  34  of the metal strip  19 . Exceptional heat transfer into the metal strip  19  is accomplished by conduction due to the intimate contact of the heated block  40   a  or heated blocks  40   a  and  40   b  and the metal strip  19 .  
     [0076] Blocks  40   a  and  40   b  can be heated by one or more heating elements  45  that thermally communicate with the blocks  40   a  and  40   b . Although, FIG. 4A shows six heating elements  45  contained within the heating blocks  40   a  and  40   b , the number of heating elements  45  and their disposition are shown illustratively and the invention is not to be construed as being so limited. More or fewer heating elements  45  can be used to transfer heat to the heating blocks  40   a  and  40   b . Furthermore, the heating elements  45  do not have to be contained within the physical structure of the heating blocks  40   a  and  40   b . For example, the heating elements  45  can thermally communicate with one or more outer surfaces of the blocks  40   a  and  40   b.    
     [0077] Preferably, the heating elements  45  can be heated by gas flame and/or electrically. Alternatively, means for heating the heating elements  45 , e.g., steam, solar power, and the like, can be used without violating the scope and spirit of this invention.  
     [0078] A plurality of springs  43  is shown in FIGS. 4A and 4B. The springs  43  are used to maintain intimate contact between the heating blocks  40   a  and  40   b  and the metal strip  19  to maximize conductive heat transfer therebetween. Although, FIGS. 4A and 4B show three springs  43 , which are shown only for illustrative purposes, those of ordinary skill in the art can appreciate that the invention can be practiced using more or fewer springs  43 . Furthermore, FIGS. 4A and 4B show a plurality of springs  43  that is disposed against the upper heating block  40   a . Those of ordinary skill in the art can appreciate that the invention can be practiced using a plurality of springs  43  that is disposed against the lower heating block  40   b  or both heating blocks  40   a  and  40   b.    
     [0079] In an alternative preheating embodiment, the molten reservoir or bath  30  can be extended lengthwise upstream beyond the metal strip  19  length that is required for volumetric flow. See FIG. 2. Accordingly, exceptional heat transfer into the metal strip  19  is accomplished by conduction due to the intimate or proximal contact of the molten bath  30  and the metal strip  19 . An advantage of this embodiment over the embodiment previously described is that it uses the molten reservoir  30  to heat the metal strip  19 , which eliminates the need for a separate heating means  16 .  
     [0080] Optionally, the apparatus  10  can include a fluxing device  17 . The fluxing device  17  can be disposed generally before the preheating means  16  so as to wet the at least one of the upper and lower surfaces  34  and  38  of the metal strip  19  with a flux  50 . Typically, commercially known, acid-based fluxes  50  are applied to one or more surfaces of the metal strip  19  to remove oxidants and other contaminants, which can further enhance the adherence of molten material  15  to the metal strip  19 .  
     [0081] After the metal strip  19  has been preheated and, if desired, fluxed, the metal strip  19  enters a casting device  18  where a molten material  15  is cast onto, i.e., “wets”, one or more surfaces of the metal strip  19  in a casting device  32  and subsequently is cooled by a cooling means  20  to provide at least one desired profile  35   b.    
     [0082] The embodied casting device  18  includes a heated reservoir  30 , a casting die  32 , a conduit  33 , which communicates between the heated reservoir  30 , and the casting die  32 , and a cooling device  20 . The heated reservoir  30  is structured and arranged to contain the molten material  15  and to maintain it in a molten state. Typically, the temperature of the heated reservoir  30  is maintained at about 50 to about 100° F. above the liquidus of the material  15  that is to be cast onto the metal strip  19 . A plurality of heating elements (not shown), e.g., integrated, electrical resistance heaters, heat the reservoir  30  to maintain the material  15  in a molten state, i.e., to a temperature above the liquidus of the metal alloy. Those skilled in the art will appreciate that other means of heating the casting means  18  are possible and that the present invention is not to be construed as being limited to electrical resistance heaters.  
     [0083] The conduit  33  through which the molten material  15  can be delivered to the casting die  32  can be heated to a temperature between about 20 to about 100° F. above the liquidus of the alloy material to prevent molten material  15  from congealing in the conduit  33  before the molten material  15  reaches the casting channel  42  in the casting die  32 . Those skilled in the art will recognize that the heating temperature of the casting device  18  and the elements thereof is dependent on the composition, i.e., liquidus, solidus, and phase characteristic of the specific alloy being cast on the metal strip  19 . Conduits  33  are heated using, e.g., electrical resistance means for assured temperature control. Preferably, molten material  15  travels from the heated reservoir  30 , through the conduit  33 , to the casting die  32  by gravity flow. However, a pump (not shown) can be added to pump the molten material  15  under pressure into the casting die  32 .  
     [0084] The casting die  32  also can be heated to a temperature between about 20 to 100° F. above the liquidus of the alloy material to prevent molten material  15  from congealing against inner surfaces of the casting die  32  before the desired profile  35   b  is provided. The heating elements for the heated reservoir  30  also are capable of heating the casting die  32 .  
     [0085] Referring to FIGS. 3A to  3 D, a preferred embodiment of a casting device  18  for providing a single profile  35   b  on the upper surface  34  of a metal strip  19 , i.e., a single-sided casting device  18 , now will be described. In the illustrative embodiment, the casting die  32  and the cooling device  20  are shown as a single structure with a thermal isolation barrier  38  disposed therebetween. FIG. 3B provides a cross-sectional view of the heated strip sealing section  41  of a single-sided casting die  32 . FIG. 3C provides a cross-sectional view of the reservoir and transition zone  42  of a single-sided casting die  32 . FIG. 3D provides a cross-sectional view of the solidification zone  47  of the cooling device  20 .  
     [0086] The casting die  32  comprises an upper die portion  32   a  and a lower die portion  32   b , which can be removably attached to each other, e.g., using clamps, bolts, screws, vises, and the like. The upper and lower die portions  32   a  and  32   b  are structured and arranged so that the metal strip  19  first encounters a heated strip sealing section  41  that is disposed at a proximal, or upstream, end  44  of the casting die  32 . After the heated strip sealing section  41 , the metal strip  19  passes successively through a heated reservoir and transition zone, or casting channel,  42 , a thermal isolation zone  38 , and a solidification region  47  in the cooling device  20  before exiting the casting device  18  at a distal, or downstream, end  46 .  
     [0087] The strip sealing section  41  is disposed upstream of the casting channel  42  and substantially confines and guides the metal strip  19  before molten material  15  is cast onto, or “wets”, the metal strip  19  in the reservoir and transition zone  42 . As shown in FIG. 3B, the strip sealing section  41  comprises a cavity  37  that is disposed, e.g., in the upper die portion  32   a . Preferably, the cavity  37  extends along the entire length of the casting device  18  and the dimensions, i.e., width W 1  and depth D 1 , of the cavity  37  in the strip sealing section  41  are only slightly larger than the corresponding dimensions of the metal strip  19  so that the metal strip  19  is confined and guided within the strip sealing zone  41  without undue frictional contact between the moving strip  19  and the walls of the cavity  37 . The strip sealing section  41  and the metal strip  19  are heated by a plurality of heating elements  45  that are in thermal communication with the casting die  32 .  
     [0088] After passing through the strip sealing section  41 , the metal strip  19  enters a reservoir and transition zone  42 , i.e., a casting channel, in which molten material  15  is cast onto, i.e., “wets”, the metal strip  19  to provide, successively, a rough profile  35   a  and then a dimensionally consistent final profile  35   b . The reservoir portion of the reservoir and transition zone  42  is in communication with the conduit  33  leading to the heated reservoir  30  via one or more inlets  60 , which allows molten material  15  to gravity flow or be pumped from the heated reservoir  30  to the reservoir portion of the reservoir and transition zone  42 . One or more inlets  60  communicate further between the reservoir portion of the reservoir and transition zone  42  and the conduit  33  to provide a means for continuously communicating molten material  15  into the reservoir portion of the reservoir and transition zone  42  to provide a rough profile  35   a . Preferably, a single, circular inlet  60  having a diameter of about ½inch can ensure the necessary flow of molten material  15  to fill the reservoir and transition zone  42 .  
     [0089] The casting and bonding system  10  of the present invention can be run in a state of balance between molten material  15  being fed into the reservoir portion of the reservoir and transition zone  42  and the amount of molten material  15  that exits the transition portion of the reservoir and transition zone  42  in a preferred profile  35   b . The excess molten material  15  held in the reservoir portion of the reservoir and transition zone  42  is available for maintaining sufficient molten material  15  during any inconsistencies in flow rate.  
     [0090] Referring to FIG. 3C, the dimensions of the reservoir portion of the reservoir and transition zone  42  are structured and arranged to provide a rough profile  35   a  of molten material  15  at any desired location or locations on the upper surface  34  of the metal strip  19 . The volume of the reservoir portion of the reservoir and transition zone  42  can be increased beyond minimal volume requirements to heat the metal strip  19  further.  
     [0091] The rough profile  35   a  of molten material  15  provided in the reservoir portion of the reservoir and transition zone  42  can be characterized as providing the desired profile width W 2 , which, dimensionally is less wide than the width W 1  of the metal strip  19 , and a height H, which exceeds a desired depth D 2  of the final profile  35   b , i.e., the height H of the rough profile  35   a  in the reservoir portion of the reservoir and transition zone  42  is greater than the final depth D 2 . To confine the molten material  15 , provide a rough profile  35   a , and prevent the molten material  15  from flowing laterally across the upper surface  34  of the metal strip  19 , the shoulders  39  that define the profile width W 2  are in intimate, frictional communication with the metal strip  19  to provide a seal against the upper surface  34  of the metal strip  19 . The reservoir and transition zone  42  and the metal strip  19  are heated by a plurality of heating elements  45  that are in thermal communication with the casting die  32 .  
     [0092] After the metal strip  19  is wet in the reservoir portion of the reservoir and transition zone  42 , the metal strip  19  then moves to the transition, or tapered, portion of the reservoir and transition zone  42 . The tapered portion of the reservoir and transition zone  42  tapers, e.g., uniformly, in the direction of movement of the metal strip  19  from the maximum height H of the reservoir portion to the desired depth D 2  of the final profile  35   b . Accordingly, the rough profile  35   a  progressively shrinks vertically to provide a final profile  35   b  of the molten material  15  on the metal strip  19 . As the dimensions of rough profile  35   a  transition to the dimensions of the final profile  35   b , excess molten material  15  remains in the reservoir and transition zone  42 , which can reduce wastage and better assure that the molten material  15  completely fills the profile  35   b , especially during periods of inconsistent delivery of molten material  15 .  
     [0093] The wetted metal strip  19  with a liquidus final profile  35   b  then passes downstream of the casting channel  42  through a thermal isolation barrier  38  and then into the solidification region  47  in the cooling device  20 . The thermal isolation barrier, or slot,  38  minimizes heat transfer between the reservoir and transition zone  42  and the solidification region  47 . Moreover, the thermal isolation barrier  38  isolates the temperature gradient of the casting die  32 .  
     [0094] Preferably, the isolation barrier, or slot,  38  comprises an air gap that surrounds an enclosed die channel  62  that connects the casting die  32  to the cooling device  20 . Alternatively, the thermal isolation barrier  38  can include material with high insulating characteristics, e.g., ceramic. Preferably, the enclosed die channel  62 , which connects the transition portion of the reservoir and transition zone  42  to the cooling device  20  has substantially the same cross section and dimensions as the final profile  35   b  as it exits the transition portion of the reservoir and transition zone  42 .  
     [0095] The cooling device  20  includes a cavity  37 , e.g., in an upper block  20   a , substantially corresponding to the dimension of the metal strip  19  and the final, desired profile  35   b , that comprises a solidification zone  47  and one or more cooling channels  48 . The purpose of the cooling device  20  is to allow the molten material  15  and metal strip  19  to cool sufficiently to solidify the molten material  15  to provide a final profile  35   b  and to bond the profile  35   b  to the metal strip  19 .  
     [0096] Preferably, a coolant, e.g., cold water, oil, chilled gas, and the like circulates through a plurality of, e.g., transverse, cooling channels  48  that are disposed in the cooling device  20  to provide a temperature in the cooling device  20  of about 20 to about 150° F. below the liquidus of the molten material  15 . Preferably, the coolant is metered through the plurality of cooling channels  48  using the flow rate of the coolant, which can be metered, e.g., using pressure valves, and the ambient temperature of the coolant to balance heat removal.  
     [0097] After passing through the cooling device  20 , the metal strip  19  exits the casting device  18  through the distal end  46  and is recovered on a take-up coil  59 . The final profile  35   b  is fully solid upon leaving the cooling device  20 . Further, the final profile  35   b  is bound to the metal strip  19 . Optionally, the final profile  35   b  can be rolled or skived to correct the shape or improve the surface quality of the profile  35   b.    
     [0098] The take-up coil  59  is structured and arranged, e.g., in a windable, rotatable coil  59  of a type that is well known to the art. The coil  59  can be disposed on the take-up coiler device  12 . The take-up coiler means device  12  can comprise, e.g., a cylindrical, substantially horizontal bar or axle  53  that is rotatably attached to the apparatus  10  at, e.g., the coiling end, or to a separate support structure (not shown). The bar or axle  53  can rotate about an axis. Preferably, a drive motor (not shown) that is capable of providing any desirable rate of rotation can rotate the bar or axle  53  to facilitate the coiling, or winding, process and to provide a force to the free running end of the unwinding coil  55  to move the metal strip  19  through the various means described above.  
     [0099] Referring to FIG. 5, there is shown an illustrative example of an alternative embodiment of the single-sided casting device  18  just described. The upper die portion  32   a  and lower die portion  32   b  of this embodiment can be structured and arranged with corresponding cavities  37  and grooves  36  in the upper and lower die portions  32   a  and  32   b , respectively, rather than just having a cavity  37  in the upper die portion  32   a . Although FIG. 5 only shows a cross-section of the casting device  18  in the solidification region  47  of the cooling device  20 , those skilled in the art can appreciate and modify the above teaching in each of the other regions previously described.  
     [0100] The lower die portion  32   b  includes a guiding groove  36  for guiding and substantially, laterally confining the metal strip  19 . Preferably, the depth D 3  of the guiding groove  36  in the lower die portion  32   b  is slightly less than the thickness T of the metal strip  19  so that the upper surface  34  of the metal strip  19  extends slightly above the top surface  51  of the lower mold  32   b  and just slightly wider that the width W 1  of the metal strip  19  so that the metal strip  19  is not in continuous frictional engagement with the side walls of the guiding groove  36 .  
     [0101] The upper die portion  32   a  includes a corresponding cavity  37  for further guiding and substantially confining the metal strip  19  that also provides a desired profile  35   b . One or more inlet openings  60  communicate between the reservoir portion of the reservoir and transition zone  42  and the conduit  33  to provide a means for continuously communicating molten material  15  into the reservoir portion of the reservoir and transition zone  42  to provide a rough profile  35   a . Preferably, the upper die portion  32   a  is maintained at a temperature that prevents congealing of the molten material  15  before the molten material  19  has filled up the entire profile  35 .  
     [0102] To confine the molten material  15  from flowing laterally across the upper surface  34  of the metal strip  19 , the shoulders  39  that define the profile width W 2  of the final profile  35   b  are in intimate, frictional communication with the metal strip  19  so as to provide a seal against the upper surface  34  of the metal strip  19 .  
     [0103] In yet another embodiment (not shown), the guiding groove  36  in the lower die portion  32   b  can be structured and arranged to have substantially the same width W 1  and depth D 3  as the width W and thickness T of the metal strip  19 , respectively. The casting channel  42  in the upper die portion  32   a , then, would be structured and arranged to provide a rough profile  35   a  and a final profile  35   b . Once again, to confine the molten material  15  from flowing laterally across the upper surface  34  of the metal strip  19 , the shoulders  39  that define the profile width W 2  of the final profile  35   b  are in intimate, frictional communication with the metal strip  19  so as to provide a seal against the upper surface  34  of the metal strip  19 .  
     [0104] Referring to FIG. 6A, an embodiment of a casting device  18  for providing final profiles  35   e  and  35   f , respectively, on the upper surface  34  and lower surface  38  of a metal strip  19 , i.e., a two-sided casting device  18 , now will be described  
     [0105] The strip sealing section  41 , reservoir and transition zone  42  and solidification zone  47  of the present embodiment are substantially the same as those described above for the single-sided casting device  18  with the following modifications and alterations. Referring to FIG. 6B, the strip sealing section  41  includes upper and lower die portions  32   a  and  32   b  having an upper cavity  37   a  and a lower cavity  37   b , respectively. Preferably, the cavities  37   a  and  37   b  are reverse mirror images that extend the entire length of the casting die  32 . More preferably, the depths D 3  of the cavities  37   a  and  37   b  are substantially the same and, moreover, approximately equal to one-half the thickness T of the metal strip  19 .  
     [0106] Referring to FIG. 6C, in the reservoir and transition zone  42 , the upper mold  32   a  and the lower die portion  32   b  also can be reverse mirror images of each other. The upper die portion  32   a  can include a first pair of equalization channels  52   a  that are structured and arranged to match up with a corresponding second pair of equalization channels  52   b  that are structured and arranged in the lower die portion  32   b . The plurality of equalization channels  52   a  and  52   b  provide communication between the upper cavity  37   a  and the lower cavity  37   b  so that molten material  15  can flow therethrough to provide a rough upper profile  35   c  on the upper surface  34  of the metal strip  19  and a rough lower profile  35   d  on the lower surface  38  of the metal strip  19 .  
     [0107] Preferably, the equalization channels  52   a  and  52   b  are continuous longitudinally along the length of the reservoir and transition zone  42  of the casting die  32 . Alternatively, the equalization channels  52   a  and  52   b  can comprise a plurality of discrete channels that are disposed at some, e.g., uniform, interval or intervals along the length of the reservoir and transition zone  42  of the casting device  32 . More preferably, in the transition, or tapered, portion of the reservoir and transition zone  42 , the equalization channels  52   a  and  52   b  also are tapered, e.g., uniformly, in the direction of movement of the metal strip  19 . As provided before, both the upper and lower die portions  32   a  and  32   b  are heated to ensure that the molten material  15  does not congeal in the cavities  37   a  and  37   b  or the equalization channels  52   a  and  52   b  before the molten material  15  wets the metal strip  19  and fills out the final profiles  35   e  and  35   f.    
     [0108] Once sufficient molten material  15  wets the metal strip  19  in the reservoir and transition zone  42  and provides final profiles  35   f  onto the upper and lower surface  34  and  38  of the metal strip  19 , the metal strip  19  then passes through the thermal isolation barrier  38  and enters the solidification region  47  of the cooling device  20 , which expedites the solidification of the molten material  15  and bonds the molten material to the metal strip  19  to provide profiles  35   e  and  35   f  thereon. Preferably, a coolant, e.g., cold water, oil, chilled gas, and the like, circulates through a plurality of, e.g., transverse, cooling channels  48   a  and  48   b  that are disposed in at least one of the upper and lower cooling blocks  20   a  and  20   b  in the cooling device  20  to provide a temperature of the cooling means  20  of about 20 to about 150 ° F. below the liquidus of the molten material  15 . Preferably, the coolant is metered through the plurality of cooling channels  48   a  and  48   b  using flow rate of the coolant, which can be metered, e.g., using pressure valves, and the ambient temperature of the coolant to balance heat removal.  
     [0109]FIG. 2 provides yet another embodiment of the apparatus  10  wherein preheating, casting, and cooling take place with the metal strip  19  in a substantially vertical orientation. For reasons that will become obvious to one of ordinary skill in the art, a vertical orientation is ideal for two-side casting as it eliminates the need for equalization channels  52   a  and  52   b.    
     [0110] All of the elements of the substantially vertical embodiment are the same or substantially the same as like numbered elements of the previously described, substantially horizontal orientation, i.e., FIG. 1, and the two-side casting device  18 , i.e., FIG. 6A. By orienting the metal strip  19  vertically, equalization of flow between the upper and lower cavities  37   a  and  37   b  becomes less problematic as does thermal balancing of the upper and lower die portions  32   a  and  32   b . Furthermore, equalization channels  52   a  and  52   b  are not required in the upper and lower die portions  32   a  and  32   b.    
     [0111] Molten material  15  can be introduced at or near a proximal, e.g., top, end  44  of the casting device  32  and/or a conduit  33  that is in communication therewith by disposing a single reservoir  30  above the point at which the edges of the metal strip  19  are initially engaged by the cavities  37  and  36  of the strip sealing section  41 . Hence, molten material  15  is free to flow completely around both the upper and lower surfaces  34  and  38  of the metal strip  19 . The reservoir portion of the reservoir and transition zone  42  typically is filled with molten material  15  by positioning the outlet conduit  33  directly over the open top of the reservoir portion of the reservoir and transition zone  42 . Alternatively, if oxidation of the molten bath  30  becomes a problem, the conduit  33  can be structured and arranged so that molten material  15  enters the reservoir portion of the reservoir and transition zone  42  through a side inlet  60 .  
     [0112] The vertically-oriented casting apparatus  10  of FIG. 2 further includes a plurality of, e.g., two, deflector rolls  25  that are used to re-direct the metal strip  19  from a substantially horizontal orientation to a substantially vertical orientation and then back to a substantially horizontal orientation. The plurality or rolls  25  can be idle coilers or can be driven rolls that provide a pulling force to further pull the metal strip  19 .  
     [0113] Although preferred embodiments of the invention have been described using specific terms, such descriptions are for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claims.