K-0530 Ni基単結晶超合金CMSX-2の高温疲労強度(S04-4 非鉄金属の組織と疲労特性)(S04 金属材料の組織と疲労強度信頼性)

概要

論文の詳細を見る
A nickel-based single-crystalline superalloy, CMSX-2 was investigated from the standpoint of high temperature fatigue strength. Three kinds of push-pull fatigue tests were conducted at 1000℃: (1) PP-test under a sinusoidal stress waveform of 1 Hz-frequency at stress amplitude of 300MPa, the number of cycles to rupture, N_f=8,234, (2) CC-test under a trapezoidal one with hold time in tension and compression of 600s each at stress amplitude of 250MPa, N_f=93, and (3) PP_<preCC>-test, which is PP-test carried out after removal of surface oxide film and small cracks generating during preceding CC-test for 47 cycles, N_f=4,318. A distinguished microstructural difference between PP and PP_<preCC> is that γ'-phase kept the initial cubic shape in PP but it changed to spherical in PP_<preCC>-Nearly 10%-increase in total strain range and 50%-decrease in fatigue life of PP_<preCC> as compared with pure PP-fatigue is attributable to the collapse of γ'-phase.
一般社団法人日本機械学会の論文
2001-08-22