Analysis For Mechanical Behavior Of Gcr15/Pmma Under Torsional Fretting Wear

Torsional fretting is the relative motion with a tiny amplitude between the contact interfaces induced by reciprocating torsion under alternate load. It is one kind of failure behavior which is not allowed to be neglected, as a result of wildly existing in many fields such as aerospace industry and automotive industry. The damages forms of fretting can be defined as wear and fatigue according to the loading cases. There is great significance in the research of fretting damage whose harm becoming gradually obvious. The current research on fretting damage is very active. Lots of achievements in the experiment were obtained, especially experimental research for Tsinghua University and Southwest Jiaotong University etc, which developed a completed system of experiment after a lots of exploration. Those achievements confirmed reciprocally and further analyzed fretting damage mechanism. However, little research has been made in FEM simulation. In this paper, a ball-plate contact geometry of GCrl5/PMMA was studied, and mechanical behavior on the contact surface was analyzed by a finite element code. The simulation results were compared to the results of experiments.(1)The finite model of GCr15/PMMA was established by FEM software MARC, and the stress-strain distribution was analyzed under different angular displacement and fiction coefficient. Results showed that angular displacement and friction coefficient had great influence on the stress and strain of the contact area.(2)The analyses in quality were taken to friction torque-angular displacement curves, worn scars micrographs and wear scars profiles of GCrl5ball and PMMA which were obtained by torsional fretting experiments. Results showed that the friction torque of the same cycle was bigger with the increasing angular displacement, and the corresponding wear depth and range were also bigger.(3) The simulation results and the test results were compared under the torsional fretting, and good consistency was obtained between the two kinds of results. It indicated that the FEM method could be used to predict the torsional fretting of GCrl5/PMMA.