| 摘要 |
A cold work steel has the following chemical composition in weight %: 1.25-1.75% (C+N), however at least 0.5% C 0.1-1.5% Si, 0.1-1.5% Mn, 4.0-5.5% Cr, 2.5-4.5% (Mo+W/2), however not more than 0.5% W, 3.0-4.5% (V+Nb/2), however not more than 0.5% Nb, not more than 0.3% S, the rest is iron and unavoidable impurities, and a microstructure of thissteel in the hardened and tempered conditions of the steel contains 6-13 vol. % of vanadium-rich MX-carbides, -nitrides and/or carbonitrides which are evenly distributed in the matrix of the steel, where X is carbon and/or nitrogen, at least 90 vol. % of said carbides, nitrides and/or carbonitrides having an equivalent diameter, Deq, which is less than ; and totally not more than 1 vol - % of other existing carbides, nitrides or carbonitrides. |
