Sliding abrasion wear assessment of Al2O3 - SiC nanocomposite coatings

Abstract

The present work describes abrasion wear tests that were carried out on low carbon steel test wheels coated with a series of high velocity oxygen fuel (HVOF) and plasma sprayed Al2O3-SiC nanocomposite coatings with varying SiC contents. These were compared with pure Al 2O3 coatings applied by HVOF and with uncoated steel. The HVOF sprayed coatings exhibited consistently superior abrasion wear resistance compared with plasma sprayed coatings of equivalent composition and were much better than uncoated steel. Overall, the HVOF Al2O3-10SiC nanocomposite coating showed the best abrasion resistance of all the coatings tested. They were worn very slowly by a microabrasion process. The poor performance of the plasma sprayed coatings was attributed to inefficient in flight melting of the particle agglomerates during the deposition process. This resulted in coatings with a low cohesive strength, which made them particularly vulnerable to particle pull out during abrasion testing. © 2003 IoM Communications Ltd. Published by Maney for the Institute of Materials, Minerals and Mining.