抄録
In order to toughen brittle materials, shotblasting process at room temperature was performed, followed by annealing at high temperature. During annealing, fine cracks, which were introduced by shotblasting process, disappeared and dislocation cells were formed. Brittle materials were toughened by the crack propagation prevention effect of dislocation cells. Toughness was evaluated by measuring fracture toughness value K_<IC>, and It was 1.4 to 4 times the rate of an improvement of the fracture toughness K_<IC> after toughening process.
