Dry Sliding Wear Behavior of AZ91 Alloy Processed by Rotary-Die Equal Channel Angular Pressing

This research examines the effect of wear testing parameters on the wear behavior of AZ91 alloy prepared through rotary-die equal channel angular pressing (RD-ECAP). An AZ91 alloy was processed by RD-ECAP method at 573 K for up to 16 passes to reduce the grain size to similar to 5 mu m. The properties of the alloys produced by RD-ECAP were compared with the as-received alloy. In order to measure the wear behavior of RD-ECAP manufactured alloy with the as-received alloy, wear tests were performed using ball-on-disk apparatus with specific loading conditions and varying sliding speeds. Surface analysis was used to show the presence of delamination, wear debris and plowing using scanning electron microscopes (SEM). The findings showed that, due to the grain refinement and homogeneity of the second phase distribution, RD-ECAP processed magnesium alloys possess increased wear resistance compared to the initial condition (unprocessed alloy), which makes them suitable for applications in aerospace, automotive and structural industries. Besides, the weight loss reduced with the increase of RD-ECAP pass numbers. Furthermore, increasing in applied load had a more dramatic effect on wear resistance compared to increasing sliding speed and sliding time.