The surface integrity of a die steel after electrodischarge machining: 2 residual stress distribution

Abstract

The residual stresses produced in the surface layers of KEA145 (AISI H13) tool steel specimens during electrodischarge machining have been measured by the bending-deflection method. Stress-depth profiles were obtained through progressive removal of material by electropolishing. High residual tensile stresses were found in all specimens, decreasing from a maximum - at the surface for the finishing generator and 20 μm below the surface for the roughing generator - to zero at a depth of about 200 μm. The magnitude of the residual stress increased with pulse energy. © 1991 The Institute of Metals and the Wolfson Institute for Surface Engineering.