Numerical Prediction of the Microstructure and Stress Evolution During Surface Grinding of AISI 52100 (DIN 100Cr6)

Abstract

AbstractGrinding is one of the most important finishing processes in industrial production. During grinding, the workpiece is subjected to thermomechanical loads. Thermal damage can occur in terms of microstructure changes due to a critical temperature history. A holistic model of the relevant physical load fields and their interactions would help describe and predict the influence of grinding loads on the residual stresses in the surface zone of the workpiece. In this paper, a very promising approach is introduced to simulate grinding of the hardened and tempered bearing steel AISI 52100 using the Finite Element Method (FEM). A material model was developed to describe the thermomechanical and metallurgical changes of the bearing steel under the process loads. Material properties were modeled depending on the temperature and microstructure changes. Temperature gradients, microstructure evolution, thermal, and phase transformation strains were integrated in the model to predict the residual stress state after grinding. Experimental and simulative investigations were conducted for pendulum grinding, and the measured and simulated residuals stresses were compared. The depth of the subsurface zone, where thermally influenced microstructural changes occur, varied with changes of the process parameters. Experiments and simulations showed compressive stresses in the re-hardened zone and tensile stresses in the tempered area.