Wire rod for 5000 MPa-grade diamond wire and production method therefor

A method for producing a wire rod for a 5000 MPa-grade diamond wire, wherein the wire rod comprises the following chemical components in percentage by mass:

• 1.01% to 1.10% of C, 0.15% to 0.40% of Si, 0.30% to 0.60% of Mn, 0.01% to 0.40% of Cr, and either or both of 0.0005% to 0.0020% of B and 0.01% to 0.09% of V;
• the balance of Fe and unavoidable impurities, wherein the impurities comprise less than or equal to 0.003% of Al, less than or equal to 0.0008% of Ti, less than or equal to 0.005% of S, less than or equal to 0.008% of P, less than or equal to 0.0010% of O and less than or equal to 0.0020% of N;
• and the production method comprises the following processes:
• vacuum melting:
• melting molten steel by adopting a vacuum melting furnace in an atmosphere with a pressure in the furnace below 10 Pa, and casting same into a steel ingot;
• steel ingot remelting:
• processing the steel ingot by adopting either or both of electroslag remelting and vacuum arc remelting to obtain a remelted ingot, wherein the electroslag remelting is carried out under a protective atmosphere, and a remelting speed of the vacuum arc remelting is 3.0 kg/min to 3.5 kg/min;
• billet making and grinding:
• cogging or forging the remelted ingot into a steel billet, and grinding the steel billet;
• wire rolling:
• rolling the steel billet to form the wire rod, with a start rolling temperature of 1030° C. to 1060° C., and a finish rolling temperature of 950° C. to 1020° C.;
• and
• cooling:
• carrying out temperature-controlled cooling on the wire rod on a cooling line comprising at least four fans, starting and controlling an air quantity of each of the 1st to 4th fans to be 80% to 100% of a maximum rated air quantity of each of the 1st to 4th fans.