Tribological Behaviour of Transparent Spinel (MgAl2O4)

The wear behaviour of transparent magnesium aluminate (MgAl2O4) was investigated for unlubricated sliding against chrome steel balls under different load (5, 10, and 15 N) conditions. The sliding speed and sliding distance were retained constant, i.e., 260 mms-1 and 157 m, respectively. The coefficient of friction (COF) varied from 0.56 to 0.66 in the investigated sliding wear conditions. It was found that wear rate increased with an increase in load. The worn surfaces show that material removal for selected sliding conditions is mainly by abrasion, cracking, and grain pull-out. SEM and EDS analysis of the counterbody and the debris formed during sliding was executed. Subsurface analysis of the worn surfaces of MgAl2O4 was also performed to understand the material removal mechanism. The experimentally measured wear rate was tried to fit a model.