粒子の斜め衝撃によるセラミックスの損傷

抄録

In order to make clear the effect of tangential component of impact force on the particle impact damage of ceramics, a silicon carbide or steel particle was impacted obliquely on a silicon carbide specimen at various impact angles.
For low impact velocity, partial ring cracks were initiated on the surface of specimen. With an increase in impact velocity, they became completely closed ring cracks, and an alignment of the non-concentric ring cracks along the impact direction was observed on the surface of specimen at the impact site.
The oblique particle impact produced an cone crack inclined with respect to the normal of the surface. Therefore, the residual strength of specimen evaluated by the bending test after particle impact was dependent on the impact direction. The residual strength of transversely impacted specimen was smaller than the case of longitudinally impacted one in the high impact velocity range. An explanation for the tangential component of impact on the inner damage could be given by using the static sliding contact model from the viewpoint of fracture mechanics.
However, the extent of surface damage and the decrease in residual strength were generally depended upon the normal component of impact velocity, regardless of impact angle of particle.