Static and Impact Shear Strength Estimation of a Continuous Carbon Fiber-Reinforced Silicon Nitride Using Double Notched Specimens

Fumiko SUGIYAMA, Kinya OGAWA, Toshihiko NISHIDA
1996 Journal of the Ceramic Society of Japan  
Finite element analysis was performed to investigate the shear stress distribution in double notched isotrop ic and orthotropic specimens under compressive loading. The shear stress distribution between the notches in the orthotropic material was found to be relatively uniform except at the notch roots where a distinct stress concentration was predicted at both for the isotropic and the orthotropic materials . In brittle or thotropic materials, microcracks initiate in the adjacent regions to
more » ... notch roots and may relax stress con centration. Static and dynamic tests were performed on double notched specimens of continuous carbon fiber-reinforced silicon nitride ceramics. The shear strength in the fiber direction is much lower on the per pendicular plane than on the parallel plane to the hot pressing direction. The strain rate dependencies of the shear strength were clarified through the present method. It is found that the shear strength evaluated by this method was much lower than that evaluated by conventional tests, such as the short beam or the com pression tests.
doi:10.2109/jcersj.104.978 fatcat:uyaj4ncwyrgkhebvajr7qgpyta