Abstract
The purpose of this study is to clarify the possibility of the sphere indentation test to evaluate properties of crack initiation and wear progress in ceramic thin films deposited on cemented carbide. Three kinds of ceramic thin films were deposited onto cemented carbide WC-Co substrates. Cyclic sphere indentation tests were carried out by using spherical indenter to investigate the aspects of crack initiation, wear progress in ceramic film and to obtain the influence of the applied maximum load P_<max> and load ratio L_s on the cyclic number of crack initiation N_i and wear value in thin films. The main conclusions are the following. (1) The loading cycle of ring crack initiation N_i increase with increasing L_s. (2) The wear value of S=S/(d_1-d_2) linearly increase accordance with P_<max> and loading cycles N, where S is obtained by measuring the cross-sectional shape of contact area and d_1, d_2 are diameter of wear region in the contact area. (3) The values of S^^-/(P_<max>×N) is almost constant independent of L_s, P_<max> and N.
