| 摘要 |
PURPOSE:To improve toughness without degrading hardness and wear resistance by dispersing MC carbide into a cast iron base which is specified in the contents of respective elements and values of Cr/C and W/Mn and consists of tempered martensite and residual austenite. CONSTITUTION:The cast iron compsn. is composed, by weight %, of 1.5-2% C, 15-25% Cr, 1-3.5% W, 1.5-4% Mn, 1-1.5% Si, 0.2-1% Mo, 0.2-1% V, and the balance Fe and has the structure consisting of the temperature martensite and the residual austenite. The M7C3 carbide of about 13-36% area rate is crystallized in the base by such compsn. by which the wear resistance is improved. On the other hand, the M23C6 carbide is controlled to 8-20% area rate, by which the toughness is improved. The wear resistance and toughness are further improved if 0.5-1% Ni and 0.5-1% >=1 kinds among Co, Nb and Ti are incorporated at need into such cast iron.
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