The Study of Hypervelocity Gouging Based on the Material Point Method

Gouging is a large nonlinear deformation phenomenon experienced in rail materials under severe loading conditions such as the tremendous heating caused by frictional effects at the slider/rail interface. The material point method (MPM) algorithm is designed specifically to solve such nonlinear, large deformation problems. The theories and steps of the MPM algorithm are described in this paper, and an investigation of hypervelocity gouging is conducted using the MPM algorithm. Because of frictional heating near the contact region, the effects of temperature on the gouge development are evaluated by several developed thermal environment scenarios. Moreover, the regular patterns of gouging at various impact velocities, horizontal velocities, and friction coefficients are analyzed. The results show that the MPM algorithm can successfully simulate the gouging phenomenon. With the gouge initiation and development, the temperature rapidly increases to the melting temperature, and the yield stress rapidly decreases at the gouge location. The regular patterns of gouging provide a new effective method for antigouging research.