Prediction of Wear and Plastic Flow in Rails - Test Rig Results, Model Calibration and Numerical Prediction

Artikel i vetenskaplig tidskrift, 2011

Conventionally, laboratory measurements under idealized conditions are used to establish parameters needed in different kinds of wear models. This paper presents a procedure for determining the Archard's wear coefficient from data collected in a full-scale wheel-rail test rig, i.e. under realistic loading conditions. Moreover, a simulation procedure capable of simulating rail profile evolution in conformal contacts incorporating both wear and plasticity is presented. In each simulation step, dynamic responses are calculated using the commercial vehicle-track interaction software GENSYS. The conformal contact is treated by applying a multi-Hertzian approach. To account for plastic deformations, a 20 elasto-plastic FE analysis is carried out in conjunction with a 3D local contact analysis in the commercial finite element (FE) software ABAQUS. It is shown that, due to the conformal contact, elastic shakedown is obtained after only a few load cycles and is therefore disregarded in the subsequent analyses. Quantitatively good results, in terms of worn-off area and shape of the worn profile, are presented for simulations between 20k and 100k load cycles. However, dependence between the chosen wear step length and the profiles obtained from the simulations is found.