Cryo-Treated Blanking Punch Life Improvement Analysis

Abstract

Cryogenic treatment is a secondary process to traditional heat treatment used for improving the hardness and wear resistance of tool steels. Though the potential use of cryogenic treatment on AISI D2 tool steel under laboratory conditions has been well established by the researchers, it is essential to do the analysis to ensure its sustainable use for industrial application. Therefore, impact of cryogenic treatment on AISI D2 steel blanking punch was evaluated in terms of increase in production rate and its life. The cryogenically treated D2 tool steel punches were used and subjected to manufacture the control levers using blanking operations.  The improved wear resistance of cryogenically treated punch resulted in increase in production and punch life more than 200%. Punch life was studied and correlated to increase in production & wear behavior of blanking punch. The AISI D2 steel samples were prepared and subjected to laboratory tests comprising of metallographic observations and hardness. It was found that laboratory tests were not enough to predict improvements in mechanical properties. The mechanism responsible for augmented wear resistance by cryogenic treatment was the conversion of retained austenite to martensite and precipitation of new secondary carbides.