High-vanadium high-speed steel and preparation method therefor, and use thereof

Abstract

The present disclosure provides a high-vanadium high-speed steel and preparation method therefor, and use thereof, which relate to the technical field of high-vanadium high-speed steel. The preparation method includes: smelting raw materials to form a melt; impacting the melt to a cooling platform to form a high-vanadium high-speed steel casting billet; and performing a spheroidizing annealing treatment and a quenching and tempering treatment, so as to obtain a resultant. The spheroidizing annealing treatment includes: heating the high-vanadium high-speed steel casting billet to 820-910° C.; holding for 2-4 h; then cooling down to 450-550° C. at a cooling rate larger than 40° C./h; and then air cooling to a room temperature.

1 . A preparation method of a high-vanadium high-speed steel, comprising:
 smelting raw materials to form a melt, wherein the raw materials in mass percentage comprise C: 2.0-2.5%, Cr: 4-6%, W: 2.5-6%, Mo: 3-7%, V: 4-10%, Si: 0.3-0.6%, Mn: 0.3-0.8%, and a balance of Fe;   impacting the melt to a cooling platform to form a high-vanadium high-speed steel casting billet;   carrying out a spheroidizing annealing treatment on the high-vanadium high-speed steel casting billet to obtain an annealed ingot, wherein the spheroidizing annealing treatment comprises heating the high-vanadium high-speed steel casting billet to 820-910° C.; holding for 2-4 h; then cooling down to 450-550° C. at a cooling rate larger than 40° C./h; then air cooling to a room temperature; and   performing a quenching and tempering treatment on the annealed ingot, so as to obtain a resultant.   
     
     
         2 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein the cooling rate is 45-75° C./h. 
     
     
         3 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein the high-vanadium high-speed steel casting billet is heated with a furnace in a tube furnace protected by an inert gas. 
     
     
         4 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein the raw materials are smelted by using an intermediate frequency induction furnace at a smelting temperature of 1480-1520° C.; the intermediate frequency induction furnace is vacuumized to 100-400 Pa when smelting; and subsequently the inert gas is filled for protection. 
     
     
         5 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein a pressure difference between an inner chamber of the melt and an outer chamber during the melt impacting is 0.05-0.25 MPa, and a spraying speed is 0.75-1.75 m/s. 
     
     
         6 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein a speed of the cooling platform moving downward is 50-120 mm/s. 
     
     
         7 . The preparation method of the high-vanadium high-speed steel according to  claim 1 , wherein the quenching and tempering treatment comprises: preheating the annealed ingot at 600-750° C. for 5-15 min; then carrying out a quenching and holding a temperature at 1000-1230° C., wherein a holding duration is 10-30 min, and carrying out the quenching in oil to a room temperature; and then tempering 1-4 times at 520-600° C. for 1 h each time, wherein the tempering is carried out each time after air cooling to the room temperature. 
     
     
         8 . The preparation method of the high-vanadium high-speed steel according to  claim 7 , wherein the annealed ingot is preheated in a muffle furnace, and quenched in a tube furnace filled with an inert atmosphere. 
     
     
         9 . A high-vanadium high-speed steel, wherein the high-vanadium high-speed steel is prepared by using the preparation method of the high-vanadium high-speed steel according to  claim 1 . 
     
     
         10 . A use of the high-vanadium high-speed steel according to  claim 9  in a preparation of a roll, a hammer head, a ball mill liner, or a rotor body. 
     
     
         11 . The high-vanadium high-speed steel according to  claim 9 , wherein an annealing hardness of the high-vanadium high-speed steel is 315-360 HV. 
     
     
         12 . The high-vanadium high-speed steel according to  claim 9 , wherein a tempering hardness of the high-vanadium high-speed steel is 863-980 HV. 
     
     
         13 . The high-vanadium high-speed steel according to  claim 9 , wherein a tempering bending strength of the high-vanadium high-speed steel is 1157-1404 MPa. 
     
     
         14 . The high-vanadium high-speed steel according to  claim 9 , wherein a vanadium content in the high-vanadium high-speed steel is 4-10%. 
     
     
         15 . The high-vanadium high-speed steel according to  claim 9 , wherein after the high-vanadium high-speed steel is annealed, vanadium carbide in the ingot is in a shape of sphere, and is uniformly distributed in a base. 
     
     
         16 . The high-vanadium high-speed steel according to  claim 9 , wherein after the high-vanadium high-speed steel is tempered, vanadium carbide in the ingot is in a shape of sphere and block, and is distributed dispersedly, wherein vanadium carbide with a coarse size and an irregular shape does not appear.