Observation of the Failure Mechanism for Diamond-like Carbon Film on Stainless Steel under Tensile Loading

Hyun-Jong Kim, Myoung-Woon Moon, Dong-Ik Kim, Kwang-Ryeol Lee, Kyu-Hwan Oh
 

The study investigated fracture behaviours of the cohesive cracking and subsequent buckling delamination at the interface between a diamond-like carbon (DLC) film and stainless steel substrate during tension test. It was revealed by cross-sectioning analysis with a focused ion beam system that spallation of the DLC film was caused by an interfacial cracking and a subsequent kinking into thin film layer. Interfacial adhesion strength was estimated by the spalled crack width, which shows that the adhesion of the DLC coating was considerably improved by increasing the negative bias voltage during Ar plasma etching prior to the film deposition.