| 摘要 |
PROBLEM TO BE SOLVED: To provide a nitrided powder high speed tool steel having a high level of hardness, toughness and wear resistance.SOLUTION: The nitrided powder high speed tool steel is provided which contains, by mass%, C:0.70 to 1.5%, Si:2.0% or less, Mn:1.0% or less, Cr:3.0 to 7.0%, Mo:5.0 to 8.0%, W:5.0 to 8.0%, V:6.0 to 9.0%, Co:5.0 to 15%, N:0.50 to 2.5% and the balance Fe with inevitable impurities, and which satisfies ΔC:-1.0 to 2.0 and has a hardness of 68 HRC or more, is excellent in toughness and wear resistance, provided that Mo and W are (2Mo+W):16 to 23% in the above described range and further ΔC=C*-Ceq, C*=C+(6×N)/7...(1) and Ceq=0.06×%Cr+0.063×%Mo+0.033×%W+0.2×%V+0.1×%Nb...(2).SELECTED DRAWING: None |
