| 摘要 |
PROBLEM TO BE SOLVED: To provide a steel for metal mold and a metal mold in which the coarsening of austenite crystal grain during hardening heating can be prevented to increase the toughness after the hardening and tempering, and in which the heat conduction capability is high.SOLUTION: Said steel is obtained by making the steel composition contain, in mass%, 0.35<C<0.55, 0.01<Si<0.20, 1.50<Mn<1.80, 1.80<Cr<2.00, 0.90<Mo<1.30, 0.61<V<1.20 and 0.0004<N<0.0500, and the balance be Fe and unavoidable impurities, to produce a steel having a hardness of 25 to 55 HRC, the old austenite crystal grain size number before transformation of 5 or more, and the heat conductivity λ [W/m/K] at 25°C as measured by using laser flash method, of 29≤λ≤42.SELECTED DRAWING: None |
