Metallic Cellular Materials Produced by 3D Weaving

Although it was developed primarily as a method to produce integral thick preforms for composites, 3D weaving provides an intriguing industrial scale manufacturing path to form cellular metal materials. In typical composites applications, development focused on increasing the volume fraction of fibers (yarns) within the preform. To produce effective cellular materials instead, research must focus on how to create open space within the woven structure. As a demonstration of this manufacturing path, small Cu wires, and then NiCr wires, were woven into several materials with various internal architectures using a non-crimp 3D orthogonal weaving machine. Initially, techniques were developed to weave the individual metal wires with precise placement and minimal twisting. These techniques were then used to create several different 3D woven material architectures with regular interconnected internal open space. Subsequent processes, such as brazing, soldering, and electroplating would be used to bond the nodes where the wires contact each other. In this set of experiments, the materials were 30 mm wide, 3-4 mm thick and on the order of a meter long. However the techniques should be scalable to meters in width, centimeters in thickness, and tens of meters in length.