Enhancement on the Tool Steel's Surface Properties by Eta Carbide Distribution Mechanism of Cryogenic Treatment

摘要

In this study, the effect of cryogenic treatment on microstructural, mechanical, and tribological properties of AISI L2 steel was investigated. Heat treatment processes conducted were, as directly quenched (C), quenched tempered (CT), and quenched cryogenically treated (CC), and the last group (CCT) was additively tempered. The volume fraction of retained austenite, the percentage of carbide density, hardness, empiric fracture toughness, the coefficient of friction (COF), and adhesive/abrasive wear resistance were determined according to the relevant standards. The retained austenite ratio decreased for the CCT process which also reduced the distance between carbides, and it increased the carbide density. A drastic improvement was observed in the tribological behavior of CC and CCT samples. CCT process increased the operational service life of steel in mold making applications due to high adhesive wear resistance, while the CC process provided the best solution for cold cutting operations due to the highest abrasive wear resistance.