Magnesia partially stabilized zirconia wire drawing die assembly

Abstract

The present system provides a wire drawing die assembly having a magnesia oxide partially stabilized zirconia die or nib for contacting or reducing the diameter of a wire during a draw. The magnesia partially stabilized zirconia has a density of approximately 5.75-5.90 g/cc; a fracture toughness of approximately 10-12; and a flexural strength of approximately 575-700 MPa.

1 . An apparatus comprising:
 (a) a wire drawing die having a forming passage, the wire drawing die being partially stabilized zirconia.   
     
     
         2 . The apparatus of  claim 1 , wherein the partially stabilized zirconia is a magnesia partially stabilized zirconia. 
     
     
         3 . The apparatus of  claim 1 , wherein the partially stabilized zirconia is a monolithic magnesia partially stabilized zirconia. 
     
     
         4 . The apparatus of  claim 1 , wherein the wire drawing die is configured as a nib. 
     
     
         5 . The apparatus of  claim 1 , further comprising a casing having a through aperture, the through aperture sized to receive the wire drawing die. 
     
     
         6 . The apparatus of  claim 1 , further comprising a casing having a through aperture, the through aperture sized to receive the wire drawing die, the casing including one of (i) a shoulder projecting inwardly into the through aperture, the shoulder sized to contact the wire drawing die and (ii) a taper sized to contact the wire drawing die. 
     
     
         7 . The apparatus of  claim 1 , further comprising a casing having a through aperture and a bushing sized to be received within the through aperture, the bushing sized to receive the wire drawing die. 
     
     
         8 . The apparatus of  claim 1 , wherein the partially stabilized zirconia is monolithic. 
     
     
         9 . A method comprising:
 (a) reducing a diameter of a metal wire by passing the wire through a wire drawing die formed of a partially stabilized zirconia; and   (b) collecting a reduced diameter wire after passing through the wire drawing die.   
     
     
         10 . The method of  claim 9 , wherein the wire drawing die is magnesia partially stabilized zirconia. 
     
     
         11 . The method of  claim 9 , wherein the metal wire is ferrous. 
     
     
         12 . The method of  claim 9 , wherein the wire drawing die is monolithic. 
     
     
         13 . An improved method of drawing a surface treated wire to the reduced diameter, the improvement comprising:
 (a) passing a length of the surface-treated wire through a die formed of a magnesium oxide partially stabilized zirconia.   
     
     
         14 . The improved method of  claim 13 , wherein the magnesium oxide partially stabilized zirconia is monolithic. 
     
     
         15 . The improved method of  claim 13 , further comprising providing a forming surface of the magnesium oxide partially stabilized zirconia to pass the wire substantially free of striations.