Experimental Studies on the Grind-Hardening Effect in Cylindrical Grinding

Abstract

In recent years high-strength and high-temperature alloys are used for structural and other applications. These newer high-performance materials are inherently “more difficult to machine” and also necessitate the need for higher dimensional and geometrical accuracy. Grinding is one of the most familiar and common abrasive machining processes used for the finishing operation. Compared to other machining processes such as turning, milling, etc., the specific energy developed during grinding is very high. At a critical level of specific grinding energy, the temperature rise[1]1. Des Ruisseaux , N.R. and Zerkle , R.D. 1970. Thermal analysis of the grinding process. Trans. ASME J. Eng. Ind., 92: 428–432. View all referencesexperienced by the workpiece may be such that thermal damage is induced. Heat damage induced by the grinding process is well documented and may be categorized by temper colors that are at least unsightly and probably indicative of more serious damage, including thermal cracks, tempered zone, etc.,[2]2. Shaw , M.C. and Vyas , A. 1994. Heat affected zones in grinding of steels. Ann. CIRP, 43/1: 571–581. View all referenceswhich can lead to catastrophic failure of critical machine parts that shortens the life of products subject to cyclic loading. In this work, a new heat treatment process called “grind hardening” and a mathematical model are introduced, and this work deals with how the in-process energy in grinding can be effectively utilized to improve the surface hardness and surface texture, and also to prevent damages. An experimental study has also been carried out in grinding AISI 6150 and AISI 52100 steels with an alumina wheel, and the results are discussed.