Effects of Abrasive Particle Type, Load and Sliding Distance on Micro-Abrasion Resistance of High Speed Steel Coated with AlCrN or AlTiN

High Speed Steel (HSS) specimen surfaces were coated with AlCrN and AlTiN via Physical Vapor Deposition (PVD) method for the micro-abrasion wear behavior testing. Wear tests were performed by fixed ball micro-abrasion wear equipment. During the micro-abrasion wear tests, 0.5, 1 and 1.5 N loads were applied for periods of 60 and 180 seconds. In these tests, different kinds of abrasives were used, as alumina (Al2O3) and silicon carbide (SiC). Two different particle sizes were used for each type of abrasive, which are F800 (mean size 6.5 +/- 1 mu m) and F1200 (mean size 3.0 +/- 0.5 mu m). During the wear tests, wear loss increased with increasing SiC and Al2O3 abrasive particle size. It was determined that the volume losses formed by SiC abrasive particles on AlTiN and AlCrN coatings to be higher than Al2O3 abrasive particles. Micro-grooving and micro-rolling wear mechanisms were observed when F800 and F1200 abrasive slurry were used, respectively. Volume losses increased with the increase in the applied load and the number of cycles. The AlCrN coatings exhibited better wear resistance than the AlTiN coatings. The applied test load had a significant effect on the wear mechanisms observed.