Method for producing metal nanofibers, yarns and textiles
View Patent ↗A method for fabrication of nanometer scale metal fibers, followed by optional further processing into cables, yarns and textiles composed of the primary nanofibers. A multicomponent composite is first formed by drilling a billet of matrix metal, and inserting rods of the metal desired as nanofibers. Hexed or round rods can also be inserted into a matrix metal can. The diameter of this composite is then reduced by mechanical deformation methods. This composite is then cut to shorter lengths and reinserted into another billet of matrix metal, and again the diameter is reduced by mechanical deformation. This process of large scale metal stacking followed by mechanical deformation is repeated until the desired fiber size scale is reached, the fibers being contained in the matrix metal. After size reduction, the composite metal wires may be further processed into built up configurations, depending on intended application, by stranding, cabling, braiding, weaving, knitting, felting, etc., to form yarns or textiles. After the built up configuration is formed, the matrix metal is removed by chemical etching, leaving a cable, yarn or textile composed of the primary nanofibers.
1. A method of forming nanofibers of metals or metal alloys comprising the steps of: inserting rods comprising fiber metal or alloy into holes drilled into a matrix metal billet, mechanically deforming this billet to a rod of smaller size, then restacking these smaller rods into a subsequent matrix metal billet; and
repeating the steps multiple times until the rods have been reduced to nanofibers of a desired diameter.
2. The method of forming nanofibers as in claim 1 wherein the restacked rods are round and inserted into drilled holes in the subsequent matrix metal billet.
3. The method of forming nanofibers as in claim 1 wherein the nanofibers are removed from the matrix metal by selectively etching the matrix using an acid that attacks the matrix but not the nanofiber.
4. A method in accordance with claim 1 , further including forming integrated nanofiber structures by additional processing of nanofibers contained in wires produced, followed by stranding, cabling, braiding, wearing, knitting or felting to form yams or textiles.
5. The method of forming integrated nanofiber structures as in claim 4 , wherein the nanofibers are removed from the matrix metal by selectively etching the matrix using an acid that attacks the matrix but not the nanofibers.
6. The method of forming integrated nanofiber structures as in claim 5 , wherein polymer impregnation is used to strengthen and immobilize the nanofibers in a nanofiber structure.
7. A method of forming nanofibers of metals or metal alloys comprising: forming rods of hexagonal or round cross-section wherein longitudinally extending nanofiber metal is encased within a surrounding matrix metal; bundling the said rods together and inserting them into a can of matrix metal to form a billet; mechanically deforming said billet to a rod of smaller size, then restacking a plurality of said smaller rods into a subsequent matrix metal billet; and repeating said restacking and deforming steps multiple times until the rods have been reduced to where the nanofibers are of a desired diameter.
8. A method in accordance with claim 7 wherein the nanofibers are removed from the matrix metal by selectively etching the matrix using an acid that attacks the matrix but not the nanofibers.
9. A method in accordance with claim 7 , further including forming integrated nanofiber structures by additional processing of nanofibers contained in wires produced, followed by stranding, cabling, braiding, wearing, knitting or felting to form yams or textiles.
10. A method in accordance with claim 9 wherein the nanofibers are removed from the matrix metal by selectively etching the matrix using an acid that attacks the matrix but not the nanofibers.
11. A method in accordance with claim 10 , wherein polymer impregnation is used to strengthen and immobilize the nanofibers in a nonofiber structure.
12. A method in accordance with claim 1 or claim 7 wherein the metal or metal alloy is gold or a gold alloy.
13. A method in accordance with claim 1 or claim 7 wherein the matrix metal is copper or a copper alloy.
14. A method in accordance with claim 3 or claim 8 wherein the acid is nitric acid.