Metal fiber yarn with enhanced strength and processability

Abstract

A new metal fiber yarn and methods for obtaining such a yarn are provided. The metal fiber yarn constitutes a construction comprising continuous metal fibers forming a metal fiber yarn. The construction comprises at least 5 bundles of continuous fibers, whereof at least one bundle is a bundle of metal fibers, preferably bundle drawn metal fibers. The bundles of continuous fibers are twisted together to form a yarn. Each bundle of metal fibers comprises at least 30 metal fiber filaments. The length of the continuous fiber bundles is substantially equal per unit length of the metal fiber yarn and the length of the fiber bundles per unit length of the metal fiber yarn is larger than the unit length of the metal fiber yarn itself.

1 . A metal fiber yarn comprising at least 5 bundles of continuous fibers ( 7 ), said bundles being twisted together, said at least 5 bundles of continuous fibers ( 7 ) comprising at least one bundle of continuous metal fibers, each of said at least one bundle of continuous metal fibers comprising at least 30 continuous metal fibers, characterized in that the length of said bundles of continuous fibers ( 7 ) is substantially equal per unit length of said metal fiber yarn and that the length of said bundles of continuous fibers ( 7 ) per unit length of said metal fiber yarn is larger than the unit length of said metal fiber yarn. 
     
     
         2 . A metal fiber yarn according to  claim 1 , wherein said at least one bundle of continuous metal fibers are bundle drawn metal fibers. 
     
     
         3 . A metal fiber yarn according to  claim 1 , wherein said bundles of continuous fibers all have the same twist direction and the same cabling angle. 
     
     
         4 . A metal fiber yarn according to  claim 1 , wherein all of said at least 5 bundles ( 7 ) are continuous metal fiber bundles. 
     
     
         5 . A metal fiber yarn according to  claim 1 , wherein at least part of said at least one bundle of continuous metal fibers comprises continuous stainless steel fibers. 
     
     
         6 . A metal fiber yarn according to  claim 1 , wherein at least part of the metal fibers in said metal fiber bundles have a cross section comprising at least two concentric metal layers. 
     
     
         7 . A metal fiber yarn according to  claim 6  wherein the core of said fibers is copper and the outer layer is stainless steel. 
     
     
         8 . A metal fiber yarn according to  claim 6  wherein the core of said fibers is stainless steel and the outer layer is copper. 
     
     
         9 . A metal fiber yarn according to  claim 1 , wherein the amount of said metal fiber bundles in the metal fiber yarn is equal to or less then 30. 
     
     
         10 . A metal fiber yarn according to  claim 1 , wherein the amount of metal fibers per bundle is less than 2500. 
     
     
         11 . A metal fiber yarn according to  claim 1 , wherein said continuous metal fibers have an equivalent diameter in the range of 8 to 30 μm. 
     
     
         12 . A metal fiber yarn as in  claim 1 , wherein said metal fiber yarn further comprises a coating, preferably PVC, PVA, PTFE, FEP, MFA, or polyurethane lacquer. 
     
     
         13 . Use of the metal fiber yarn as in  claim 1  as resistance heating elements in heatable textile applications. 
     
     
         14 . Use of the metal fiber yarn as in  claim 13 , wherein said heatable textile application is car seat heating. 
     
     
         15 . Use of the metal fiber yarn as in  claim 1  as a reinforcement element.