Powder metallurgy wear-resistant tool steel

Abstract

A powder metallurgy wear-resistant tool steel includes chemical components by mass percent of: V: 12.2%-16.2%, Nb: 1.1%-3.2%, C: 2.6%-4.0%, Si: ≤2.0%, Mn: 0.2%-1.5%, Cr: 4.0%-5.6%, Mo: ≤3.0%, W: 0.1%-1.0%, Co: 0.05%-0.5%, N: 0.05%-0.7%, with balance iron and impurities; wherein a carbide component of the powder metallurgy wear-resistant tool steel is an MX carbide with a NaCl type face-centered cubic lattice structure; wherein an M element of the MX carbide comprises V and Nb, and an X element comprises C and N.

What is claimed is: 
     
       1. A powder metallurgy wear-resistant tool steel, comprising chemical components by mass percent of: V: 13.0%-16.0%, Nb: 1.2%-2.5%, C: 2.8%-3.7%, Si: ≤1.3%, Mn: 0.2%-1.5%, Cr: 4.8%-5.4%, Mo: ≤2.0%, W: 0.1%-0.5%, Co: 0.1%-0.4%, N: 0.05%-0.4%, O: ≤0.008%, with balance iron and impurities; wherein a carbide component of the powder metallurgy wear-resistant tool steel is an MX carbide with a NaCl type face-centered cubic lattice structure; wherein an M element of the MX carbide comprises V and Nb, and an X element comprises C and N;
 wherein in the chemical components of the powder metallurgy wear-resistant tool steel, a V equivalent is V eq : 13.0%-16.0%, wherein V eq =V+0.65 Nb. 
 
     
     
       2. The powder metallurgy wear-resistant tool steel, as recited in  claim 1 , wherein the impurities comprise S, wherein a S content is no more than 0.1%. 
     
     
       3. The powder metallurgy wear-resistant tool steel, as recited in  claim 2 , wherein the impurities comprise P, wherein a P content is no more than 0.03%. 
     
     
       4. The powder metallurgy wear-resistant tool steel, as recited in  claim 3 , wherein a volume fraction of the MX carbide is 16%-25%. 
     
     
       5. The powder metallurgy wear-resistant tool steel, as recited in  claim 4 , wherein a size of at least 80% of the MX carbide is 0.5-1.3 μm judging from volume percentage. 
     
     
       6. The powder metallurgy wear-resistant tool steel, as recited in  claim 5 , wherein a maximum size of the MX carbide is no more than 5.0 μm.