Cryogenic Treatment and Combination of Nitriding and Cryogenic Treatment of Hot Forging Tools

Abstract:- This paper deals with cryogenic treatment and cryogenic treatment combined with nitriding of hot working tool steels. Unlike traditional steel cold treatment generally conducted at the temperatures of about-70°C for several hours, cryogenic treatment at the temperature of about minus-180°C for several dozen hours was performed. Basing on a dilatometric and differential thermal analysis (DTA) the authors made an attempt to explain the process of changes resulting from cryogenic treatment. In addition, the authors, basing on test results, discussed comparatively the effect of cryogenic treatment on the resistance to wear at high temperatures and on the hot working tool steel hardness. The presented results confirm the rise of material durability of drop forging dies after cryogenic treatment or nitriding combined with cryogenic treatment