Influence of Surface Roughness on Fatigue Life of AISI D3 Component Hard Turned by CBN Insert under Dry Machining

Abstract

Hard turning has been broadly attributed as a surrogated process for customary grinding because it facilitates any intricate profiles with a single setting. It is a precise machining process, that could accomplish remarkable dimensional accuracy, geometrical tolerance and surface finish, and also ensures coolant-free machining for super hardened steels and alloys. Still, the parts produced are affected by the adverse surface integrity along with a surface pattern often called a White Layer. As a result, the parts produced are affected by fatigue life due to cyclic loads. This investigation was attempted to analyse surface roughness against the Fatigue life of AISI D3 component hard turned by semi-worn out CBN insert under the dry machining. L27 orthogonal array was designed with three cutting speeds, feed rates and depth of cuts. ANNOVA table was formed and found that the feed rate influenced around 62.4% on the surface roughness, subsequently depth of cut impacts nearly 26.6% and cutting speed implies 11%. In addition, it was revealed that the surface roughness influences the Fatigue life of the part. The lowest surface roughness has produced highest Fatigue life of 2.8×107 cycles.