Modeling of white layer thickness in high speed machining of hardened steel based on phase transformation mechanism

Abstract

White layer formed in high speed machining of hardened steel has great effects on the performance of products, so it is imperative to predict the thickness of white layer precisely. Combined with finite element method, a prediction model for white layer thickness based on phase transformation mechanism is proposed. The thermal–mechanical effects, as well as the effects of alloying elements, stress, and strain on phase transformation are taken into account. The theoretical derivation of the real phase transformation temperature during machining is also presented, which indicates that during cutting process, the phase transformation occurs at temperatures below the nominal austenitizing temperature. A finite element model of orthogonal cutting based on ABAQUS/Explicit™ is established. The thickness of white layer in machined surface of AISI 52100 hardened steel is predicted based on the data extracted from the finite element models, and the predictions are found to be in good agreement with experimental values. Besides, the relationship between the thickness of white layer and cutting parameters is obtained and analyzed explicitly, which provides theoretical basis for optimizing cutting parameters.