The thermally tempered glass has strong resistance for the surface crack, because the residual compressive stress exists near the surface of the glass. However, it also has the residual tensile stress in the center of the glass. Fracture behavior of the thermally tempered glass depends on the distribution of the residual stress. We examined the impact fracture behavior of the tempered glass using the Extended Distinct Element Method (EDEM). From numerical results for the normal glass and tempered glass, it is demonstrated that the thermally tempered glass is broken to many pieces by the residual tensile stress.
