1. School of Mechanical Engineering; Liaoning Shihua University; No.1 Dandong Road Fushun 113001 China
2. Materials Fatigue and Fracture Division; Institute of Metal Research; Chinese Academy of Sciences; 72 Wenhua Road Shenyang 110016 China
3. Superalloy Division; Institute of Metal Research; Chinese Academy of Sciences; 72 Wenhua Road Shenyang 110016 China