Title: Influence of hardness ratio on scratch failure of coatings

Authors: K.H. Lau, K.Y. Li, Y-W. Mai

Addresses: Department of Manufacturing Engineering and Engineering Management (MEEM), Advanced Coatings Applied Research Laboratory (ACARL), City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR. ' Department of Manufacturing Engineering and Engineering Management (MEEM), Advanced Coatings Applied Research Laboratory (ACARL), City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR. ' Centre for Advanced Materials Technology (CAMT), School of Aerospace, Mechanical and Mechatronic Engineering J07, The University of Sydney, Sydney, NSW 2006, Australia

Abstract: The effects of hardness ratio of coating to substrate on the scratching characteristics of four different kinds of coatings (Al, W, TiN and Ti1-xAlxN) deposited on aluminium, tungsten carbide and three types of M42 high speed steel were investigated. Based on the observed failure modes on the scratch tracks using scanning electron microscopy, coating failure maps consisting of regions of no failure, mixed failure and total coating break-through are constructed. The loading required for a particular failure mode decreases with increasing hardness ratio.

Keywords: scratch tests; hardness ratio; coatings; failure maps; coating hardness; substrate hardness; surface engineering; aluminium; tungsten carbide; high speed steels.

DOI: 10.1504/IJSURFSE.2007.013618

International Journal of Surface Science and Engineering, 2007 Vol.1 No.1, pp.3 - 21

Published online: 09 May 2007 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article