Abstract: A beaded preform includes a plurality of adjacently positioned beads for forming a plurality of voids in an engineered material. The beaded preforms may be comprised of a filaments (single strand of beads) and mats (two-dimensional and three dimensional arrays of beads). The filaments and mats may be coated to become tows and laminates, respectively, which may then be assembled into composite materials. The preforms may be produced using novel manufacturing apparatuses and methods, and incorporated into known manufacturing processes to produce porous structures, including stress-steering structures, in any material including metals, plastics, ceramics, textiles, papers, and biological materials, for example. Permanent bead material is preferably made of polyacrylonitrile, carbon fiber, or graphite.
Abstract: A beaded preform includes a plurality of adjacently positioned beads for forming a plurality of voids in an engineered material. The beaded preforms may be comprised of a filaments (single strand of beads) and mats (two-dimensional and three dimensional arrays of beads). The filaments and mats may be coated to become tows and laminates, respectively, which may then be assembled into composite materials. The preforms may be produced using novel manufacturing apparatuses and methods, and incorporated into known manufacturing processes to produce porous structures, including stress-steering structures, in any material including metals, plastics, ceramics, textiles, papers, and biological materials, for example. Permanent bead material is preferably made of polyacrylonitrile, carbon fiber, or graphite.
Abstract: A load bearing structure having a set of uniform voids functions to resolve the forces imposed by developing compression in the material having the voids and minimizing the amount of tension developed in the material. The voids are deployed to encompass a matrix of points arranged such that each point is spaced an equal distance from twelve and only twelve adjacent matrix points. If the structure is considered to be composed of a closely packed set of hypothetical rhombic dodecahedra (RD) and the four-edge vertices of each of those hypothetical RDs is truncated, the result will be a set of cubic voids. The center of each of those cubic voids will define the matrix referred to above and the cubic voids will serve to provide the optimum resolution of stress which minimizes the development of tension in the material. One in four of the hypothetical RDs can be eliminated achieving the same force resolution in a structure containing less material.