SiO₂の材質影響を考慮した静疲労き裂進展速度の理論式

抄録

A closed form expression of crack velocity of static fatigue of SiO₂ is derived taking into account the effects of material properties such as Young’s modulus, whose values are considerably different among SiO₂ materials made under different fabrication conditions. The calculated results of this expression show that the crack velocity is controlled by the transport process of atmospheric H₂O molecules to the crack tip and has high dependency of temperature in usual velocity range in the case of high Young’s modulus materials. On the other hand, in the case of low Young’s modulus materials, the crack velocity is controlled by the reaction process of crack tip atomic bond with H₂O molecules and has high dependency of humidity.