Abstract:
A method of inserting z-axis reinforcing fibers into a multi-layer composite laminate. Layers of material made up of z-axis fiber and y-axis fibers are automatically transported into a z-fiber deposition machine having a housing with upper and lower surfaces. Z-axis apertures are formed in the respective upper and lower surfaces. An elongated solid rod having a tapered front tip is aligned in close proximity to the aperture in the bottom surface. The rod is first rotated by a motor and then actuated upwardly completely through the thickness of the layer of x-y material by an actuator. A first hollow tube having a z-axis is axially aligned with the aperture in the top surface and a fiber bundle is threaded downwardly through a first hollow tube to a position adjacent its bottom end. The z-fiber deposition machine has structure to feed a predetermined length of the fiber bundle downwardly through the first hollow tube so that it follows the pathway in the x-y material formed by the rod which is now withdrawn downwardly through the aperture in the bottom wall. The z-axis fiber is thus deposited into the x-y material. The top end of the z-axis fiber is then severed and the x-y material is then advanced a predetermined distance to complete the cycle and is, thus, set to be repeated.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This patent application is a continuation application of U.S. patent application Ser. No. 11/530,859 filed Sep. 11, 2006, now U.S. Pat. No. 7,387,147, which is a continuation application of U.S. patent application Ser. No. 10/705,047 filed Nov. 10, 2003, now U.S. Pat. No. 7,105,071, which is a continuation-in-part application of U.S. patent application Ser. No. 09/922,053 filed Aug. 2, 2001, now U.S. Pat. No. 6,645,333, and claims the priority of provisional patent application 60/281,838 filed Apr. 6, 2001 and provisional patent application 60/293,939 filed May 29, 2001. All of the above applications are incorporated by reference herein as though set forth in full. 
    
    
     This invention was made with United States Government support under Cooperative Agreement 70NANB8H4059 awarded by NIST. The United States Government has certain rights in the invention. 
    
    
     BACKGROUND OF THE INVENTION 
     The invention relates to a method of producing a composite material and more specifically a process for incorporating z-axis fiber reinforcement into x-y axis composite material. 
     Traditional composite materials are made up of resin matrix material and a quantity of 2-dimensional fibers, continuous in the x-y axis directions, but laminated in layers to produce a material thickness. Composite material construction, wherein a fiber material such as glass fiber, carbon fiber, or aramid fiber is combined with a matrix material, such as thermoplastic or thermoset resins, is an example of a traditional 2-dimensional structure. The resulting structure is produced from “layering” of the 2-dimensional material (known as plies). Because the matrix is weaker in strength than the fiber (in many cases by at least an order of magnitude), the failure mechanism of these composites when test loaded toward their ultimate strength is a cracking or buckling or separation of the matrix material. When this occurs, the composite is known to have delaminated, or the layers of fiber material have separated. 
     Attempts have been made to lace or tie multiple layers of 2-dimensional composite materials together with z-axis directional fibers which tie all of the layers together. By doing this, delamination can be delayed or eliminated. Some techniques that have been used include 3-D braiding, 3-D weaving, and z-axis pinning. All of these methods have deficiencies, drawbacks and are expensive and labor intensive. 
     The Fusco et al U.S. Pat. No. 5,589,015 is directed to a method and system for inserting reinforcing pins in composite structure. Ultra sound energy is applied to the pins and pressure is applied simultaneously to insert the pins into the composite structure to join two laminates or reinforce a single composite structure. 
     The Childress U.S. Pat. No. 5,935,680 is directed to an interlaced z-axis pin sandwich structure that utilizes a plurality of z-axis pins that extend through the core and into each of the face sheets. The pins are arranged in an interlaced configuration off-normal to provide crack resistance around fasteners for connecting the composite structure to other structural elements in aerospace applications. 
     The Boyce et al U.S. Pat. No. 4,808,461 discloses a translaminar reinforcement structure that utilizes z-axis reinforcing elements and the method for driving these reinforcing elements into the composite structure as it is subjected to an elevated temperature and decomposes. 
     The Campbell et al U.S. Pat. No. 5,789,061 discloses a stiffener reinforced assembly and its method of manufacturing. The Boyce et al U.S. Pat. No. 5,667,859 also discloses the use of joining composite parts by including reinforcing elements that pass through the thickness of two composite adherents to be joined. The Campbell et al U.S. Pat. No. 5,827,383 also discloses a stiffener reinforcement assembly and its method of manufacturing. 
     Other patents that teach the use of tow members that are encapsulated within the foam core and which extend between the opposing face sheets to form a combined composite structure are the Boyce et al U.S. Pat. No. 5,624,622 and the Boyce et al U.S. Pat. No. 5,741,574. The Boyce et al U.S. Pat. No. 5,186,776 teaches a technique for translaminar reinforcement and the method includes heating and softening the composite laminates by ultrasonic energy and then inserting reinforcing fibers therein. 
     It is an object of the invention to provide a novel method of inserting an unstable reinforcing fiber into a composite laminate for z-axis reinforcement. 
     It is also an object of the invention to provide novel machinery for inserting an unstable z-axis reinforcing fiber into a composite laminate. 
     It is another object of the invention to provide a new type of composite material with substantial z-axis fiber reinforcement. 
     It is a further object of the invention to provide a novel method for producing layer quantities of 3-D bar stock, sheet and composite sandwich structure in a continuous, automated fashion. 
     SUMMARY OF THE INVENTION 
     The method of inserting an unstable reinforcing fiber into a composite laminate for z-axis reinforcement of the laminate requires a z-axis fiber deposition material. The side plates of the chamber formed between top and bottom plates into which is fed x-y axis material. The side plates of the chamber restrict the edges of x-y axis material. There would be multiple laterally spaced z-axis fiber deposition machines so that multiple z-axis fibers could be deposited into the x-y axis material at the same time. Each would have its own respective aperture in the top plate and the bottom plate and these would be aligned. Below each aperture in the bottom plate is an elongated solid rod having a tapered front tip. This rod is known as the “pathway deposition probe” (PDP). The PDP is rotated by a motor and then actuated upwardly through the aperture in the bottom plate, the x-y axis material and the aperture in the top plate. Mounted above each aperture in the top plate is a movable hollow tube whose initial position has its bottom end slightly inserted into the aperture in the top plate. Z-axis fiber bundles are contained on stationary rolls and are free to be drawn from the rolls continuously. The front end of each z-axis fiber bundle is threaded downwardly through one of the movable hollow tubes to a position adjacent its bottom end. There would be structure to resupply a predetermined length of z-axis fiber bundle to each movable hollow tube as a new length is needed. 
     After the PDP has been actuated upwardly to its upper most position, it is then retracted downwardly to its initial position and simultaneously, the movable hollow tube would travel downwardly through the hole created in the x-y axis material. While this is happening, the tip of the PDP would remain inserted into the bottom end of the movable hollow tube to insure a smooth entry of the hollow tube through the aperture in the x-y axis material created by the PDP. Each z-axis fiber deposition unit has a mechanism for preventing withdraw of z-axis fiber from the x-y axis material when the movable hollow tube is withdrawn upwardly. Once the movable hollow tube has been raised to its upper position, the top end of z-axis fiber that has been inserted into the x-y axis material is severed. This would complete a whole cycle. Simultaneously, across the width of the housing each of the other z-axis fiber deposition units would have completed their cycle. Next, the x-y axis material is stepped forwardly to provide a new position for the z-axis fibers to be deposited. Alternatively, the method could provide structure for stepping the housing rearwardly instead of stepping forwardly the x-y axis composite material. 
     After the x-y axis material has had the z-axis fibers deposited therein, it travels forwardly to a pultrusion die. Here the heated die cures the composite material of the plies and it exits the dies as a cured 3-D fiber composite material. The material is pulled from the die continuously by the alternate gripping edges of multiple grippers that are attached to motion control hydraulic cylinders. 
     It should be noted, the x-y material may be impregnated with resin prior to the insertion of 3-D fiber, may be impregnated with resin after the insertion of 3-D fiber, or may be impregnated with “pre-preg” resin at the factory where the x-y material was made and/or the 3-D fiber material was made. In the later case, no resin impregnation would be needed in the process, either before or after the insertion of the 3-D fiber material. 
     Another aspect of the invention involves a method of inserting a z-axis reinforcing fiber into a composite laminate for z-axis reinforcement of the composite laminate. The method includes providing at least one layer of material made up of x-axis fibers and y-axis fibers prior to incorporation of a z-axis reinforcing fiber into the at least one layer of material; the at least one layer having a top surface, a bottom surface and a predetermined thickness; providing an elongated pathway deposition device having a front tip, a shank portion, a rear end and a z-axis and positioning the front tip of the pathway deposition device in close proximity to one of the top or bottom surfaces of the at least one layer of material; providing an elongated moveable z-axis fiber insertion element having a front end, a rear end, an inner wall surface and a z-axis; positioning the front end of the moveable z-axis fiber insertion element in close proximity to the other of the top or bottom surfaces of the at least one layer of material; providing a z-axis reinforcing fiber bundle having a front end and inserting the front end of the z-axis reinforcing fiber bundle into the rear end of the moveable z-axis fiber insertion element until it travels substantially to the front end of the moveable z-axis fiber insertion element; inserting the pathway deposition device into and through the at least one layer of material a predetermined distance; temporarily securing the z-axis reinforcing fiber bundle to the inner wall of the z-axis fiber insertion element so that the z-axis reinforcing fiber bundle will move with the z-axis fiber insertion element; moving the z-axis fiber insertion element in the z-axis direction until the front end of the z-axis fiber insertion element meets with the tip of the pathway deposition device; moving the z-axis fiber insertion element and the z-axis reinforcing fiber bundle secured thereto through the entire thickness of the at least one layer of material while at the same time withdrawing the pathway deposition device from the at least one layer of material; unsecuring the z-axis reinforcing fiber bundle from the inner wall of the z-axis fiber insertion element and then withdrawing the z-axis fiber insertion element from the at least one layer of material, thus causing the z-axis reinforcing fiber bundle to remain within the at least one layer of material as the z-axis fiber insertion element is withdrawn; and severing the z-axis reinforcing fiber that is within the at least one layer of material from the z-axis reinforcing fiber bundle. 
     Another aspect of the invention involves a method of providing a z-axis reinforcing fiber into a composite laminate for z-axis reinforcement of the composite laminate. The method includes providing at least one layer of material made up of x-axis fibers and y-axis fibers prior to incorporation of a z-axis reinforcing fiber into the at least one layer of material; the at least one layer having a top surface, a bottom surface and a predetermined thickness; providing an elongated pathway deposition device having a front tip, a shank portion, a rear end and a z-axis and providing the front tip of the pathway deposition device in close proximity to one of the top or bottom surfaces of the at least one layer of material; providing an elongated z-axis fiber insertion element having a front end, a rear end, an inner wall surface and a z-axis and providing the front end of the moveable z-axis fiber insertion element in close proximity to the other of the top or bottom surfaces of the at least one layer of material; providing a z-axis reinforcing fiber bundle having a front end and inserting the front end of the z-axis reinforcing fiber bundle into the rear end of the z-axis fiber insertion element until it travels substantially to the front end of the z-axis fiber insertion element; moving the at least one layer of material so that the pathway deposition device is provided into and through the at least one layer of material a predetermined distance; moving at least one of the z-axis fiber insertion element and the pathway deposition device in the z-axis direction so that the front end of the z-axis fiber insertion element and the tip of the pathway deposition device meet; moving the at least one layer of material so that z-axis reinforcing fiber bundle and the z-axis fiber insertion element are disposed through the entire thickness of the at least one layer of material; separating the z-axis fiber insertion element and the at least one layer of material, thus causing the z-axis reinforcing fiber bundle to remain within the at least one layer of material; and severing the z-axis reinforcing fiber that is within the at least one layer of material from the z-axis reinforcing fiber bundle. 
     A further aspect of the invention involves a method of inserting a z-axis reinforcing fiber into a composite laminate for z-axis reinforcement of the composite laminate. The method includes providing at least one layer of composite laminate material prior to incorporation of a z-axis reinforcing fiber into the at least one layer of material; the at least one layer having a top surface, a bottom surface and a predetermined thickness; providing an elongated pathway deposition device having a front tip, a body portion, a rear end and a z-axis and providing the front tip of the pathway deposition device in close proximity to one of the top or bottom surfaces of the at least one layer of material; providing an elongated moveable z-axis fiber insertion element having a front end, a rear end, and a z-axis and providing the front end of the moveable z-axis fiber insertion element in close proximity to the other of the top or bottom surfaces of the at least one layer of material; providing a z-axis reinforcing fiber bundle in the moveable z-axis fiber insertion element; inserting the pathway deposition device into and through the at least one layer of material a predetermined distance; moving at least one of the pathway deposition device and the z-axis fiber insertion element in the z-axis direction until the front end of the z-axis fiber insertion element meets with the tip of the pathway deposition device; moving the z-axis fiber insertion element and the z-axis reinforcing fiber bundle through the entire thickness of the at least one layer of material while at the same time withdrawing the pathway deposition device from the at least one layer of material; withdrawing the z-axis fiber insertion element from the at least one layer of material, thus causing the z-axis reinforcing fiber bundle to remain within the at least one layer of material as the z-axis fiber insertion element is withdrawn; and severing the z-axis reinforcing fiber from the z-axis reinforcing fiber bundle. 
     A further aspect of the invention involves a method of inserting a z-x direction reinforcing fiber or z-y direction reinforcing fiber (hereinafter z-x/y) into a composite laminate for z-x/y directional reinforcement of the composite laminate. The method includes providing at least one layer of composite laminate material prior to incorporation of a z-x/y directional reinforcing fiber into the at least one layer of material; the at least one layer having a top surface, a bottom surface and a predetermined thickness; providing an elongated pathway deposition device oriented in a z-x/y direction and having a front tip, a body portion, a rear end and a z-x/y axis, providing the front tip of the pathway deposition device in close proximity to one of the top or bottom surfaces of the at least one layer of material; providing an elongated moveable z-x/y directional fiber insertion element oriented in a z-x/y direction and having a front end, a rear end, and a z-x/y axis, providing the front end of the moveable z-x/y axis fiber insertion element in close proximity to the other of the top or bottom surfaces of the at least one layer of material; providing a z-x/y directional reinforcing fiber bundle in the moveable z-x/y directional fiber insertion element; inserting the pathway deposition device into and through the at least one layer of material a predetermined distance in the z-x/y direction; moving at least one of the pathway deposition device and the z-x/y directional fiber insertion element in the z-x/y direction until the front end of the z-x/y directional fiber insertion element meets with the tip of the pathway deposition device; moving the z-x/y directional insertion element and the z-x/y directional fiber bundle through the entire thickness of the at least one layer of material while at the same time withdrawing the pathway deposition device from the at least one layer of material; withdrawing the z-x/y directional fiber insertion element from the at least one layer of material, thus causing the z-x/y directional reinforcing fiber bundle to remain within the at least one layer of material in the z-x/y direction as the z-x/y directional fiber insertion element is withdrawn; and severing the z-x/y directional reinforcing fiber from the z-x/y directional reinforcing fiber bundle. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic side elevation view of a z-axis fiber deposition unit; 
         FIG. 2  is a schematic side elevation view of a z-axis fiber deposition units integrated with the pultrusion process; 
         FIG. 3  is a schematic side elevation view of a first alternative embodiment of the z-axis fiber deposition unit; 
         FIG. 4  is a schematic partial cross section view illustrating a sandwich structure having a core covered on its top and bottom surface with respective skins formed of a x-y axis fiber material; 
         FIG. 5  is an enlarged schematic cross sectional view taken along lines  5 - 5  of  FIG. 4 ; 
         FIG. 6  is an enlarged schematic cross sectional view taken along lines  6 - 6  of  FIG. 5 ; 
         FIG. 7  is a schematic side elevation view of a z-axis fiber deposition unit integrated with the pultrusion process, where x-y material is impregnated with resin after the insertion of 3-D fiber; and 
         FIG. 8  is a schematic side elevation view of another embodiment of fiber deposition unit where fibers are deposited in the x-y composite material in the z-x/y direction. 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     The method of inserting z-axis reinforcing fibers into a composite laminate will now be described by referring to  FIGS. 1-6  of the drawings. 
       FIG. 1  shows a schematic elevation view of the novel z-axis fiber deposition process and the associated machinery. The key element of only one z-axis fiber deposition unit is illustrated in this figure. Following a description of  FIG. 1 , a more detailed, expanded description of multiple z-axis fiber deposition components will be discussed. 
     In  FIG. 1 , the cross section of a typical x-y axis material is identified by numeral  30 . Material  30  is a continuously traveling laminate of x-y axis material. The direction of pultrusion and the continuous processing is defined as being in the x-axis direction and is left-to-right. The y-axis direction is into the paper. The z-axis direction is from top-to-bottom, through 3-D material  30 . Only a few layers, or “plies” of x-y axis material  30  are shown, although clearly, additional layers could be shown. A single layer of material  30  is made up of x-axis material and y-axis material, produced by other processes prior to incorporation into the z-axis fiber deposition process. This x-y axis material could be woven glass fiber or stitched glass fiber or a combination of each, or it could be mat or unidirectional woving, or could be other fiber such as carbon or aramid. The material  30  may also be rovings. 
     Material  30  is contained in the z-axis direction by a chamber in the housing shown only by the top and bottom plates  20  and  21 , respectfully. The side plates of the housing, not shown, restrict the edges of material  30 . Since there are multiple z-axis deposition points along the y-axis, and since  FIG. 1  shows only one of these points, the edges of the chamber in the containment housing and the x-y axis material are not shown. Plates  20  and  21  are pre-spaced such that a very compact set of layers  30  are drawn through the housing, compressing the x-y axis material  30  to its nearly final z-axis directional compression prior to receiving the z-axis fiber or entering the pultrusion die. Material  30  may be impregnated with resin material and if thermoset, may be debulked prior to entering the chamber in the containment housing defined by plates  20  and  21 . 
     As stated earlier, material  30  could also be sandwich structure, without changing the operation or process. As shown in  FIG. 1 , the material  30  is a stack of layers of x-y axis fiber material, which, after deposition of the z-axis directional fiber, will be processed into the quasi-isotropic bar stock. If the material  30  is 1 inch thick (for example), there might be  36  layers of x-y axis material making up the 1-inch thickness. It would be a simple matter of construction to substitute for the middle layers of x-y axis material, a core material  28 , such as foam plastic, polyisocyanurate foam, honeycomb material, or balsa wood (see  FIGS. 4-6 ). These core materials are low density and are used in sandwich structure construction. In this manner, material  30  could have six layers of x-y axis material on the top, a core material of 0.75 inches in thickness and six layers of x-y axis material on the bottom. The z-axis fiber deposition method described herein would be identical, whether the material  30  was 100% x-y axis fiber material or a sandwich material having a core and top  27  and bottom  29  “skin” material. 
     The key elements of the z-axis fiber deposition mechanism are shown in  FIG. 1 , although all of the details of how certain mechanisms are supported or actuated are not shown. The first step of the process has the material  30  being drawn into the chamber in the containment housing between upper and lower surfaces  20  and  21 , respectfully. Material  30  is stopped because the machinery moves synchronously to the pultrusion speed. This allows the “pathway deposition probe” (PDP)  35  to be inserted through the material  30 . Alternatively, the material could be moving continuously and the deposition process could be gantry and synchronous with the pultrusion speed. The PDP  35  is an elongated solid rod having a tapered front tip, a shank portion, and a rear end. PDP  35  is first rotated by a motor  50  and then actuated upwardly by way of an actuator  61 . 
     Then the process begins in which a fiber bundle, shown by the single line  7 , is deposited in the stack of x-y axis material  30 . Although the fiber bundle is shown as a single line, in fact it could be a glass, carbon, or other fiber bundle containing hundreds or even thousands of continuous fiber filaments. This process will be referred to as the z-axis fiber deposition process. The z-axis fiber bundle  7  is contained on a stationary roll  5  which is free to be drawn continuously from the roll  5 . The fiber bundle is fed through a guidance bushing  10  and through two tubes, one of which is stationary outer tube  15  and the other a movable tube  16 . Stationary outer tube  15  and movable inner tube  16  are concentric with very close tolerances and are both penetrated at two locations to accept a fiber clamp  12 A and a fiber clamp I 2 B. Fiber clamp  12 A is by definition, stationary, as it penetrates the stationary outer tube  15 . Fiber clamp  12 B is by definition, movable, as it must move with the movement of the mechanism in the z-axis direction of the moveable inner tube  16 . Moveable fiber clamp I 2 B may or may not be extended when tube  16  is moving. The actuation mechanism of clamp  12 B is independent of the actuation mechanism for tube  16 , both of which are shown in  FIG. 1  for clarity. The purpose of fiber clamps  12 A and  12 B is to provide positive clamping of the fiber bundle to the interior of tubes  15  and  16 , respectively, at different times and for different purposes. 
     Once the PDP  35  has rotated, has been actuated in the z-axis direction, and has fully penetrated the x-y axis fiber layers  30 , the PDP  35  is not yet touching the outer movable tube  16 , but has passed completely through material  30 . At this time, the PDP  35  has stopped rotating. 
     As mentioned previously, the rotation of PDP  35  assists in the penetration of material  30  with minimum force and minimum fiber damage in the x-y axis material  30 . The next step in the process is as follows: fiber clamp  12 A is unclamped and fiber clamp  12 B is clamped. By actuating fiber clamp  12 B, in the clamped location, fiber bundle  7  is secured to the inner wall of moveable tube  16  and allows fiber bundle  7  to move with tube  16 . In an alternative embodiment, the fiber bundle  7  may not be secured to the moveable tube  16  when the tube is moved into the material  30 . For example, but not by way of limitation, the PDP  35  and tube  16  may first create a fiber bundle path in the material  30 . Once the fiber bundle path is created, the fiber bundle  7  may be inserted into this fiber bundle path, preferably through the tube  17  while the tube  17  is in the fiber bundle path. The tube  17  may then be removed from the fiber bundle path, leaving the fiber bundle  7  in the fiber bundle path in the material  30 . As the tube  17  is removed, the fiber bundle  7  may be retained by the PDP  35  or another retaining mechanism to prevent the fiber bundle  7  from accidentally being removed from the fiber bundle path with removal of the tube  17 . 
     Once clamp  12 B has secured the fiber bundle  7  to movable inner tube  16 , a mechanism (not shown) moves inner tube  16  downward in the z-axis direction until the bottom end of the tube  16  makes contact with the outside of the PDP  35  (which has already penetrated the x-y axis material  30 ) but at this time is not rotating. Alternatively, the meeting of the tube  16  and PDP  35  may occur without the tube  16  and PDP  35  making contact instead of the meeting of the tube  16  and PDP  35  occurring with the tube  16  and PDP  35  making contact as described above. 
     Next, the mechanism that moves inner tube  16 , moves fiber bundle  7  and the PDP  35  through the entire x-y axis material  30 . PDP  35  had created a pathway for inner tube  16  to be inserted through material  30 . A certain amount of low actuation force on the PDP  35  insures that the inner tube  16  stays intimate and in contact with the PDP  35 . This technique insures a smooth entry of tube  16  and the clamped fiber bundle  7  through the x-y axis material  30 . Fiber bundle  7  is pulled off the spool  5  by this process. 
     Next fiber clamp  12 B is released into the unclamped position and fiber clamp I 2 A is actuated into a clamped position. In this way, fiber clamp  12 A secures fiber bundle  7  against the interior wall of stationary tube  15 . This ensures that the fiber bundle  7  remains stationary and deposited in the x-y axis material  30 . Following this, moveable inner tube  16  is withdrawn from the x-y axis material  30  and actuated upwardly in the z-axis direction back to the original position shown in  FIG. 1 . When this step is done fiber bundle  7  does not move. Fiber bundle  7  remains as a fully deposited fiber bundle in the z-axis direction. Next, fiber bundle  7  is sheared off at the top of the x-y axis material  30  by a shear plate  25  and  26 . The stationary part of shear plate  26  never moves. The movable portion  25  is actuated by an actuator  60 . This cuts fiber bundle  7 , much like a scissors cut, and allows the fiber bundle  7 , which is carried by spool  5 , to be separated from the z-axis fiber deposited bundle (Alternatively, the z-axis fiber may be severed from the fiber bundle  7  prior to insertion instead of after insertion.). This allows a preparation for the second z-axis fiber deposition. The preparation includes adjusting the end of the fiber bundle  7  relative to the end of shear plate  26 . As shown in  FIG. 1 , the end of fiber bundle  7  is drawn slightly inwardly from the bottom end of tube  16 . This is necessary to allow the point on the tip of PDP  35  to enter tube  16  without fiber being caught between the contact points of inner tube  16  and PDP  35 . This is accomplished as follows: 
     Once sheer plate  25  has cut the deposited z-axis fiber from fiber bundle  7 , the end of fiber bundle  7  is slightly extended below the inner tube  16 . Next, fiber clamp  12 A is released and fiber clamp  12 B is actuated and clamped. Inner tube  16  is actuated further upward in the z-axis direction as shown in  FIG. 1  until the end of fiber bundle  7  is in the same relative position as that shown in  FIG. 1 . Next, clamp  12 A is actuated and clamped and clamp  12 B is released, unclamped. Following this, inner tube  16  is moved downward in the z-axis direction to the position shown in  FIG. 1 , thus that the relative position of the end of moveable inner tube  16  and the end of fiber bundle  7  is as shown in  FIG. 1 . The cycle is now set to be repeated. 
     All of the previously described operation can occur rapidly. Several units of the device as illustrated in  FIG. 1  are installed side-by-side. The movement of an entire housing containing all of the devices of  FIG. 1  occurs with the x-y axis material  30  and the plates  25  and  26  remaining stationary. In this way, for example, while the material  30  is stopped, an extra z-axis fiber can be deposited between the locations of two z-axis fibers deposited on the first cycle. A high number of z-axis fiber bundles in one row, with material  30  stationary, can in fact be deposited. Once a row, which is defined as the deposited z-axis fibers lineal in the y direction, is completed, material  30  can be moved relative to the machinery of  FIG. 1  and a second row of z-axis fibers can be deposited. This new row can have the same pattern or a staggered pattern, as required. 
     One other device in  FIG. 1  requires mentioning. Spring  40 , located at the base PDP  35  and between the PDP and the motor  50  has a special purpose. When inner tube  16  contacts PDP  35 , and then subsequently pushes PDP  35  back through the layers of x-y axis material  30 , a flaring in the end of the tube can occur, if the relative force between the two exceeds a certain value. The flaring of the end of the tube  16  will result in failure of the mechanism. Spring  40  prevents this excess differential force, thus resulting in no flaring of the end of tube  16 . 
     Although the material  30  has been described as being within the x-y plane and the tube  16  and PDP  35  moving in the z direction, alternatively, the method may include the material  30  moving in the z direction for providing the z-axis reinforcing fiber into the material  30  instead of or in addition to the tube  16  and PDP  35  moving in the z direction. For example, the method may include providing an elongated pathway deposition device  35  in close proximity to one of the top or bottom surfaces of the material  30 ; providing an elongated z-axis fiber insertion element  16  in close proximity to the other of the top or bottom surfaces of the material  30 ; providing a z-axis reinforcing fiber bundle  7  into the z-axis fiber insertion element  16 ; moving the material  30  so that the pathway deposition device  35  is provided into and through the material  30  a predetermined distance; moving at least one of the z-axis fiber insertion element  16  and the pathway deposition device  35  in the z-axis direction so that the front end of the z-axis fiber insertion element  16  and the tip of the pathway deposition device meet  35 ; moving the material  30  so that z-axis reinforcing fiber bundle  7  and the z-axis fiber insertion element  16  are disposed through the entire thickness of the material  30 ; separating the z-axis fiber insertion element  16  and the material  30 , thus causing the z-axis reinforcing fiber bundle  7  to remain within the material  30 ; and severing the z-axis reinforcing fiber that is within the material  30  from the z-axis reinforcing fiber bundle  7 . 
       FIG. 2  is a schematic side elevation view of the z-axis fiber deposition machinery integrated with the pultrusion process. The 2-D layers of x-y axis material  30  are stored on rolls  70 . They are pulled through a resin tank  31  where the 2D material is impregnated with resin. They are then pulled through debulking bushings  72  where, sequentially, the plies are stacked and each succeeding bushing  72  squeezes progressively a little more resin out of the stack of x-y axis material  30  as the x-y axis material  30  progresses toward the z-axis fiber deposition machine  73 . Once through machine  73 , the 3-D fiber composite material, now identified as numeral  31  since it has z-axis fibers deposited in it, progresses to pultrusion die  74 . Here a heated die  74  cures the 3-D fiber composite material  31  on the fly, and it exits the die  74  as cured 3D fiber composite material  32 . The material  32  is pulled from the die  74  continuously by the alternate gripping action of two grippers  75  that are attached to motion control hydraulic cylinders  76 . Cylinders  76  are CNC type cylinders and can accurately position and time the material  30  for z-axis deposition. 
     Although the x-y material  30  has be described as being impregnated with resin prior to the insertion of 3-D fiber, with reference to  FIG. 7 , the resin tank  71  may be located down-line from the z-axis fiber deposition machine  73  so that 3-D composite fiber material  31  is impregnated with resin after the insertion of 3-D fiber. Alternatively, the x-y material  30  may be impregnated with “pre-preg” resin at the factory where the x-y material  30  was made and/or the 3-D fiber material was made. In this case, no resin impregnation would be needed in the process, either before or after the insertion of the 3-D fiber material. 
     An alternative to the feed mechanism described earlier in  FIG. 1  and depicted by clamps  12 A and I 2 B, and the outer tube  15  and inner tube  16 , can be replaced by the feed mechanism illustrated in  FIG. 3 . This feed mechanism requires a more sophisticated motion control than the clamp system of  FIG. 1 , as will be evident in the description below. 
     The components of  FIG. 3  shown above the carrier plate  20  replace the components of  FIG. 1  shown above the carrier plate  20 . The key new components are a tube  16 , a urethane reel  19 , an idler bearing  18 , a spring  17 , a drive belt  22  and a CNC type motion control motor  23 . All of these components are intimately connected to a frame (not shown), which is driven through carrier plates  20  and  21 , by a CNC-type motor and ball screw (also not shown). In this way, all of the components  16 ,  19 ,  18 ,  17 ,  22  and  23  move together as a synchronous unit. 
     The embodiment illustrated in  FIG. 3  has the same fiber roll  5 , fiber tow or bundle  7 , and guidance bushing  10 . Idler bearing  18  and urethane wheel  19  provide a positive clamping of the fiber bundle  7 . Spring  17 , assures a side force of known quantity and clamps the fiber bundle  7 . When motion control motor  23  is in a locked position, not rotated, fiber bundle  7  is clamped and cannot be moved. When motor  23  is rotated, fiber bundle  7  moves relative to tube  16 , since the position of tube  16  is always the same as the other components  19 ,  18 ,  17 ,  22  and  23  of  FIG. 3 . In this way, fiber bundle  7  can either be clamped so that it can not move inside tube  16  or it can be moved inside tube  16  by rotation of the motion control motor  23 . 
     It should now be apparent that the mechanisms illustrated in  FIG. 3  can substitute for those identified in  FIG. 1 . When tube  16 , with fiber bundle  7  clamped, is moved by a CNC motor (not shown) through the x-y axis material  30 , motor  23  is not rotated. However, when tube  16  is drawn from the x-y axis material  30 , motor  23  is rotated at the exact rate of speed as the withdraw of PDP  35 . This can be accomplished with present day sophisticated motion control hardware and software. In doing this, fiber bundle  7 , stays stationary relative to x-y axis material  30 , even though tube  16  is being withdrawn. 
     The advantage of the mechanisms in  FIG. 3 , although they provide identical functions to their counterparts in  FIG. 1 , is that the speed of the process can improve by eliminating the alternative clamping of clamps  12 A and  12 B. Nevertheless, either set of mechanisms is viable for the disclosed invention. 
       FIG. 8  is a schematic side elevation view of another embodiment of a fiber deposition unit where fibers  7  are deposited in the x-y composite material  30  in the z-x/y direction. As used herein, z-x/y direction reinforcing fiber or depositing fiber  7  in the z-x/y direction means that the fiber  7  may be deposited in the x-y material  30  in the z-x direction, in the z-y direction, or the z-x-y direction. The fiber deposition unit illustrated in  FIG. 8  is similar to the z-axis fiber deposition unit described above with respect to  FIG. 3  except the fiber deposition equipment located above the x-y composite material  30  (e.g., tube  16 , urethane reel  19 , idler bearing  18 , spring  17 , drive belt  22 , CNC type motion control motor  23 ) is generally offset along the x direction (or the y direction or both the x and y direction) with respect to the fiber deposition equipment located below the x-y composite material (e.g., PDP  35 , spring  40 , motor  50 , actuator  61 ). Further, some of the fiber deposition unit equipment is disposed at an angle in the z-x/y direction (e.g., tube  16  with fiber  7 , PDP  35 ). Deposition of the fibers  7  in the x-y material  30  occurs in the same manner as that described above with respect to  FIG. 3 , except the fibers  7  are deposited at an angle in the x-y material  30  in the z-x/y direction (i.e., through the one or more layers of the x-y material, but not perpendicular to the z axis). Orienting the fibers  7  at an angle in the z-x/y direction in the x-y material  30  not only reinforces the strength of the composite material in the z direction, but increases the shear strength, shear modulus, moment of inertia of the composite material. This makes the resulting composite ideal for applications requiring flexural stiffness and shear stiffness.