The effect on wear behaviour of H13 tool steel surfaces modified using a tungsten arc heat source

The surface modification of an H13 tool steel using a tungsten are heat sou rce was studied. The investigation shows that, when surface melting was per formed in a controlled atmosphere of N-2, CO2 or CO2-Ar mixture, the wear r esistance of the surfaces was significantly enhanced over the untreated ste el. The most wear-resistant surface was that for N-2 and the least for surf aces melted in a CO2-Ar mixture. The resolidified surface microstructure co nsisted primarily of delta ferrite with some retained austenite and the inc rease in wear resistance nas attributed to an increase in surface hardness due to the formation of carbo-nitride precipitates within the modified surf aces. (C) 2000 Elsevier Science S.A. All rights reserved.