熱疲労に基因する放電加工面品質の研究 (第1報)
形彫り放電加工SKD61焼きなまし材の熱疲労特性化
1991 年 24 巻 48 号 p. 24-34
詳細
1991 年 24 巻 48 号 p. 24-34
The electric discharge machining (EDM) are effective processes for making various dies. The apparatus for EDM with high qualities and many functions have been developed recently, and it becomes possible to use them through a series of die making process. The residual solidify melt layer fomed by EDM markedly affects the life of hot die. Thermal fatigue characteristics of samples prepared by making use of EDM have been evaluated using thermal fatigue test, residual stress measurement and scanning electron microscopy. The main results are as follows; (1) The residual stress in the surface layer after EDM was tensile stress, however, it became compression stress after thermal fatigue test more than about 100 cycle. (2) The depth, width and multiplication of cracks increased in proportion to fatigue cycle.
