Adhesion measurements of chemically vapor deposited and physically vapor deposited hard coatings on WCCo substrates

• Published in: Thin solid films 1987-11, Vol.154 (1), p.361-375
• Main Authors: Jindal, Prem C., Quinto, Dennis T., Wolfe, George J.
• Format: Article
• Language: English
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Materials science; Metals, semimetals and alloys; Metals. Metallurgy; Nonmetallic coatings; Physics; Production techniques; Specific materials; Surface treatment
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/0040-6090(87)90379-8

Comparative measurements of adhesion of single-layer and multilayer hard coatings on cemented carbide substrates are made using scratch and indentation test methods. It is shown that the critical load L c in scratch adhesion is influenced by the hardness of the substrate and extraneously by the surface condition of the indenter and its coefficient of friction relative to the coating material. The average stress calculated from the width of the scratch channel is found to be a more meaningful adhesion parameter than L c. In the indentation technique, the approximate load for lateral crack initiation and the slope obtained from the indentation load-lateral crack length function are two useful adhesion parameters. The latter is demonstrated to be more discriminating in several test cases. It is also found that increased residual stress in physically vapor deposited TiN coating reduces both measured scratch and indentation adhesion parameters.