A Study on Effect of Friction Coefficient on Failure Process of Film
Titanium substrate specimen was sputter-coated with SiC or CoCrNi-oxide thin film and the wear test was carried out by using a “ball-on-disk” testing machine. The semi-circular parallel cracks appeared on the film surface with the angles of 45 degree to the sliding direction of SiC ball and the delamination of film quickly occurred after cracking. In the same study we have discussed the reason of cracking and delamination in film by FEM , and made a special effort to the effect of friction coefficient on failure process of film in this paper. With the increase in friction coefficient the high-stress area of the maximum principal stress σ1 has the trend to move towards the central trail of back-contact-edge, while the positive minimum principal stress σ3 also appears at more extensive range, the higher friction coefficient causes the higher stresses and makes the cracking and delamination more easily, where the cracks can be initiated much more near the center trail.
J. H. Zheng "A Study on Effect of Friction Coefficient on Failure Process of Film", Advanced Materials Research, Vols. 179-180, pp. 501-507, 2011