Steel wire rod having lubricating coating film that has excellent corrosion resistance and workability

Abstract

The present invention provides a steel wire rod including a lubricating coating film, which can reconcile workabilities such as wire drawability, spike property, ball ironing property and film removability, and corrosion resistance such as long-term rust prevention property. The steel wire rod includes a lubricating coating film on a surface, wherein the lubricating coating film contains a water-soluble silicate and a water-soluble tungstate, a mass ratio of water-soluble tungstate/water-soluble silicate being in a range of 0.7 to 10, and contains no phosphorus

1 . A steel wire rod including a lubricating coating film on a surface, wherein the lubricating coating film contains a water-soluble silicate and a water-soluble tungstate, a mass ratio of water-soluble tungstate/water-soluble silicate in the lubricating coating film being in a range of 0.7 to 10, and contains no phosphorus. 
     
     
         2 . A steel wire rod including a lubricating coating film containing no phosphorus, wherein the lubricating coating film is formed using a composition prepared by mixing a water-soluble silicate and a water-soluble tungstate so as to adjust a mass ratio of water-soluble tungstate/water-soluble silicate in the lubricating coating film in a range of 0.7 to 10. 
     
     
         3 . The steel wire rod according to  claim 1 , wherein the lubricating coating film contains a resin, and a mass ratio of resin/(water-soluble silicate+water-soluble tungstate) is in a range of 0.01 to 1.5. 
     
     
         4 . The steel wire rod according to  claim 3 , wherein the resin is at least one selected from a vinyl resin, an acrylic resin, an epoxy resin, a urethane resin, a phenol resin, a cellulose derivative, a polymaleic acid and a polyester resin. 
     
     
         5 . The steel wire rod according to  claim 1 , wherein the lubricating coating film contains a lubricant, and a mass ratio of lubricant/(water-soluble silicate+water-soluble tungstate) is in a range of 0.01 to 1.5. 
     
     
         6 . The steel wire rod according to  claim 5 , wherein the lubricant is at least one selected from wax, polytetrafluoroethylene, fatty acid soap, fatty acid metal soap, fatty acid amide, molybdenum disulfide, tungsten disulfide, graphite and melamine cyanurate. 
     
     
         7 . The steel wire rod according to  claim 1 , wherein the mass of the coating film per unit area of the lubricating coating film is in a range of 1.0 to 20 g/m 2 . 
     
     
         8 . The steel wire rod according to  claim 2 , wherein the lubricating coating film contains a resin, and a mass ratio of resin/(water-soluble silicate+water-soluble tungstate) is in a range of 0.01 to 1.5. 
     
     
         9 . The steel wire rod according to  claim 2 , wherein the lubricating coating film contains a lubricant, and a mass ratio of lubricant/(water-soluble silicate+water-soluble tungstate) is in a range of 0.01 to 1.5. 
     
     
         10 . The steel wire rod according to  claim 2 , wherein the mass of the coating film per unit area of the lubricating coating film is in a range of 1.0 to 20 g/m 2 .