ソーダ石灰ガラスの混合モード破壊条件
1988 年 54 巻 507 号 p. 2056-2060
詳細
1988 年 54 巻 507 号 p. 2056-2060
The mixed-mode fracture criterion of modes I and II of Soda-Lime Glass was investigated using inclined indentation surface flaws in four-point bending. In order to examine the effect of mode II on the extension of cracks, the specimens with an inclined surface flaw oriented at an angle of 45° with respect to the outer fiber tensile stress direction were fractures under hydrostatic pressure up to about 100 MPa. The obtained catastrophic fracture paths were non-coplanar with the initial flaw plane. The values of the critical stress intensity factors, KIC and KIIC, were obtained with the ratio KIIC/KIC=1.06 observed. The experimental plots of KI versus KII were compared with the existing theories. A strain energy density fracture criterion best described the mixed-mode fracture.
