高C-高Cr系冷間工具鋼の高温焼戻し硬さに及ぼすCおよびCr量の影響

概要

論文の詳細を見る
The tempering characteristics of 8 cold work die steels containing 0.6 to 1.5% C, 5 to 12% Cr, 1Mo, and 0.3V were investigated by measurements of tempered hardness after quenching or subzero treating, volume fraction of retained austenite, and by identification of precipitated carbides. The effect of C and Cr on the hardness of the steel tempered at higher temperature is summarized below, (1) The effect of vol.% of retained austenite on the amount of secondary hardening of the steels is expressed by the following equations through the parameter, K=[%Cr]-6.8×[%C]H=0.25Vγ+C, Vγ=15.2-1.05K±1.5Where H (HRC) is the amount of secordary hardening for each alloy quenched from various austenitizing temperatures, Vγ (%) is the vol.% of retained austenite in the sample, and C is a constant.(2) With increasing parameter K, the amount of secondary hardening is increased by the precipitation of M7C3 carbides.(3) With increasing parameter, L=[%Cr]+15.5×[%C], the maximum tempered hardness increases.
大同特殊鋼株式会社の論文