COLD WORKING TOOL STEEL WITH HIGH HARDNESS AND TOUGHNESS FOR COATING TREATMENT WITH CARBIDE

摘要

PURPOSE:To obtain a cold working tool steel for coating treatment with carbide provided with superior hardness and sufficient toughness by specifying the amounts of Si amd Mn and by adding C, Cr, Mo and V in a well-balanced state. CONSTITUTION:This cold working tool steel with high hardness and toughness for coating treatment with carbide consists of 0.65-0.89% C, 0.50-1.50% Si, 0.30-1.50% Mn, 8.1-10.0% Cr, 0.75-1.95% Mo, 0.5-1.0% V and the balance Fe with inevitable impurities. The growth of macrocrystals of carbide in the tool steel is inhibited by considering the balance between C and Cr, the Mo content is increased so as to obtain high hardness even after hardening and high temp. tempering, and C, Cr, Mo and V are blended in proper amounts. Accordingly, high toughness as well as high hardness is obtd. by hardening at a relatively low temp., so the tool steel is most suitable for coating treatment with carbide.