Role of material parameters in tribological stress field models

Microstructural evolution in metallic materials feedbacks with the loading conditions and the lifetime of engineering components. Tribological loading causes a complex, position-dependent, moving stress field. A systematic study is presented on the influence of the complexity of the implemented material model on the calculated stress field. For validation, results of tribological experiments on single crystals with the activation of deformation twinning are used. The calculated resolved shear stresses have to be highest on the experimentally identified twin systems. The combination of modelling and experiment shows the necessity of considering plasticity. The widely used Hamilton stress field for tribological loading is limited and based on purely elastic assumptions. The quality of the stress field is found to be sensitive to the yield strength, work hardening and plastic anisotropy. These parameters have to be carefully chosen in order to predict how a metallic material
deforms due to a sliding load.