Tungsten wire

Abstract

A tungsten wire includes tungsten as a major component. Here, 4758×D2−7258.3×D+5275.5≤T≤4758×D2−7258.3×D+6100 is satisfied where T (MPa) is a tensile strength of the tungsten wire, D (mm) is a diameter of the tungsten wire, and a roundness of the tungsten wire is at most 2.0%.

1 . A tungsten wire comprising
 tungsten as a major component, wherein   
       
         
           
             
               
                 
                   4758 
                   × 
                   
                     D 
                     2 
                   
                 
                 - 
                 
                   7258.3 
                   × 
                   D 
                 
                 + 
                 5275.5 
               
               ≤ 
               T 
               ≤ 
               
                 
                   4758 
                   × 
                   
                     D 
                     2 
                   
                 
                 - 
                 
                   7258.3 
                   × 
                   D 
                 
                 + 
                 6100 
               
             
           
         
         is satisfied 
         where T (MPa) is a tensile strength of the tungsten wire, 
         D (mm) is a diameter of the tungsten wire, and 
         a roundness of the tungsten wire is at most 2.0%. 
       
     
     
         2 . The tungsten wire according to  claim 1 , further comprising
 rhenium, wherein   a content of the rhenium in the tungsten wire is at least 0.1 wt % and at most 3 wt %.   
     
     
         3 . The tungsten wire according to  claim 1 , further comprising
 a rare earth element, wherein   a content of the rare earth element in the tungsten wire is at least 0.03 wt % and at most 0.3 wt %.   
     
     
         4 . The tungsten wire according to  claim 3 , wherein
 the content of the rare earth element in the tungsten wire is at least 0.03 wt % and at most 0.09 wt %, and   the roundness of the tungsten wire is at most 1.0%.   
     
     
         5 . The tungsten wire according to  claim 1 , wherein
 a tensile strength of the tungsten wire is at least 5800 MPa.   
     
     
         6 . The tungsten wire according to  claim 1 , wherein
 a content of the tungsten in the tungsten wire is at least 97 wt %.   
     
     
         7 . The tungsten wire according to  claim 1 , wherein
 a diameter of the tungsten wire is at most 100 μm.   
     
     
         8 . The tungsten wire according to  claim 1 , wherein
 the tungsten wire is used as a core of a saw wire.