抄録
This study is in the series of researches concerned with the mechanism of micro-deformation or fracture in brittle materials. In this paper, stress is analyzed with finite element method in the case of indentation onto the surface of MgO single crystal. Matrix is developed for the calculation which relates stress to strain in the slip process of MgO crystal. Microscopically deformed (slipped) zone is obtained from the analysis. Furthermore, it is discussed where the probability of crack growth is the highest. The main results obtained are as follows: (1) Slipped zone is constructed with a pair of slip bands which intersect with the indented surface at 45°. Its shape is approximately in accordance with experimentally observed one. (2) In the two bands just mentioned, slip occurs in the opposite directions. (3) Cracks are most likely to grow in the region between two parallel slip bands.
