Fretting wear in AZ31 magnesium alloy

Abstract

Fretting wear in magnesium alloy AZ31 was investigated in order to understand the fundamental tribological properties in magnesium alloy. Ball on disc type fretting test was conducted, in which the cyclic tangential force was applied by rotating a gear pear with the weight. The ball specimen was made of SUJ2 bearing steel, and the disc specimen was made of magnesium alloy AZ31. Normal load was applied in the range between 1000 and 2000 N, and tangential force was 100 N. It is shown in the results that the contact surface was deformed plastically after the test under static condition, and the plastic deformation increases with time. It is also found that the contact surface after the fretting test shows that wear area was occurred at the edge of contact area. Chemical reaction film was formed on the wear area, and energy dispersive X-ray spectroscopy analysis results show that the film consists of magnesium and oxygen. Slip region at the edge of contact area increased with time, and the area depends on the tangential coefficient. The maximum depth of deformed dent in fretting test at 1000 N, was greater than that in the test under static condition, and the deformation depends on the tangential coefficient.