Abstract
Evaluation method of film fracture of TiN coatings doposited by CVD and PVD was investigated under compressive load to estimate adhesive strength of the film which is important to apply ceramic coatings to instruments in engineering use. The proposed method consisted of corrosion potential monitoring and acoustic emission (AE) monitoring. The results obtained in this study are summarized as follows:
(1) Corrosion potential shift due to film fracture was recognized at higher substrate strain in CVD coatings having higher adhesive strength than in PVD coatings having lower adhesive strength.
(2) AE signal due to film fracture was also recognized at higher substrate strain in CVD coatings than in PVD coatings.
(3) Critical substrate strain at film fracture initiation estimated by corrosion potential measurement and AE monitoring methods correlated quantitatively with adhesive strength of CVD and PVD coatings.
