Diamond deposition on hardmetal substrates - Comparison of substrate pre-treatments and industrial applications

Diamond deposition on various hardmetal tools is widely used. For applications where the mechanical forces are low diamond coatings have long lifetimes, but especially for heavy duty applications the reproducibility of the diamond coating adhesion is not adequate. Wear and lifetime of diamond coated tools are determined by the diamond microstructure, the coating thickness, and the adhesion of the coating. The diamond substrate interface is important for layer adhesion, but in the case of diamond deposition on hardmetal tools, the interface can change during the diamond deposition. For this reason, surface pre-treatments are important, not only for a better diamond nucleation, but also to create a stable interface that allows good coating adhesion. The various aspects of different surface pre-treatments of hardmetal tools will be discussed. (C) 2010 Elsevier Ltd. All rights reserved.