Effect of Deep Cryogenic Treatment on Wear Behavior of Cold Work Tool Steel

Abstract

Shock resisting cold work tool steel is one of the most applicable steels for several applications such as cutting sheets, chisels, hammers, etc. It has been categorized according to its characteristic properties into different categories as hot and cold work tool steel. This work aims to study the effects of conventional and deep cryogenic treatment (DCT) on shock-resistant cold work tool steel. In this study, three alloys were cast and prepared with different carbides forming elements such as vanadium (V) and niobium (Nb). The samples were quenched in water at 900 ℃ followed by a tempering treatment at 200 ℃ for 30 min. After quenching in water, the other samples were subjected to DCT at −196 ℃ for a 5-h soaking time, followed by tempering at 200 ℃ for 30 min. To study the wear behavior of the three heats, pin-on-disc tests were used, where the sliding speed was kept constant at a value of 0.5 m/s. The normal applied loads during the wear test were 50 N and 100 N. In order to understand the wear behavior, wear tracks were studied by scanning electron microscopy, coefficient of friction and weight loss were evaluated. The results showed that the lowest average coefficient of friction was achieved by a sample of steel 3 with quenching + DCT at a load of 100 N of load by value of 0.33. A sample of steel 3 at load 50 N achieved the lowest weight loss by using DCT plus tempering. On the other hand, a sample of steel 3 achieved the lowest weight loss at 100 N by using quenching + DCT.