| 摘要 |
PROBLEM TO BE SOLVED: To provide a high-Cr cast iron superior in heat-cracking resistance for an abrasion-resistant member receiving a heat cycle involving an impact, and to provide a heat treatment method therefor. SOLUTION: The high-Cr cast iron comprises, by mass%, 2.5-3.5% C, 0.2-1.0% Si, 0.6-2.0% Mn, 11-22% Cr, 1.0-3.0% Mo, 0.01-0.15% N, and the balance Fe with unavoidable impurities, while controlling a ratio Cr/C of a Cr content to a C content into a range of 4.5 to 6.5, and a product Mn×Mo of a Mn content and a Mo content into a range of 1.8 to 2.5. The heat treatment method includes cooling the surface of the high-Cr cast iron at a cooling rate of 5°C/sec or lower in the step of quenching, to control a residualγphase in a structure to 30% or less by volume ratio. Thus, the high-Cr cast iron acquires improved heat-cracking resistance. COPYRIGHT: (C)2006,JPO&NCIPI
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