Abstract：This paper deals with DD4 single-crystal superalloy at 850℃ and 950℃ for 1000 hours of prolonged ageing. The experiments and analysis have-been carried out by picking out samples every 200 hours. The experimental results show that there isn't TCP in DD4 after 1000 hours prolonged ageing. And the microstructure is stable. The morphology and size of γ' change no much after 1000 hours prolonged ageing at 850℃,but they change a little after 1000 hours prolonged ageing at 950℃resulting in decreasing about 35% of the high temperature stress-rupture life.
周安利, 刘泽尧, 叶国胜. 长期时效对DD4单晶高温合金组织稳定性的影响[J]. 材料工程, 1997, 0(11): 9-11.
Zhou Anli, Liu Zeyao, Ye Guosheng. Influence of Prolonged Ageing about Stability of DD4 Singel Crystal Superalloy. Journal of Materials Engineering, 1997, 0(11): 9-11.