Metallurgy behind the Cryogenic Treatment of Cutting Tools: An Overview

Cryogenic treatment of cutting tool materials is widely being accepted nowadays as a complementary treatment used for enhancing the physical and mechanical properties of the material. Reports have been made regarding improvements in the wear resistance, toughness, fracture resistance, increased hardness, better thermal conductivity, lower chemical degradation and favorable residual stress condition for various grades of tool steels and tungsten carbide inserts. It is a one-time treatment that influences the entire bulk of the component, unlike surface treatments. This paper makes an effort to explain the thermodynamic phenomenon of superconductivity at the cryogenic temperatures in order to figure out why and how the changes may be occurring at atomic level in the material. Also, it summarizes the most probable metallurgical mechanisms from the literature that have been said to be responsible for the changes in the tool properties after cryogenic treatment. (C) 2015 Elsevier Ltd. All rights reserved.