【摘要】 研究了高温长期时效对一种镍基单晶合金组织和在1010℃/248MPa条件下的持久性能的影响。结果表明:950℃时效500h以前,合金的持久性能变化不大,时效1000h后合金的持久性能大幅度降低,1050℃时效100h后,合金的持久性能便开始明显下降,持久性能降低的原因是γ′相尺寸的增大及形状不规整。合金在950℃时效500h和1050℃时效100h后,γ′相开始沿不同的[100]方向长大,γ/γ′相界面能和弹性应变能的降低是γ′相长大的驱动力。更多还原

【Abstract】 The influence of microstructure after long time aging at high temperature on the stress rupture at 1010℃/248MPa was investigated. The results showed that the stress rupture properties of specimens after aging at 950℃ for less than 500h were not significantly changed, whereas the stress rupture properties were greatly reduced after aging for 1000 hours. Furthermore, the stress rupture properties begun to reduce significantly aged at 1050℃ for 500 hours due to the enlarged size of γ′ phase and its anomalous sha pe. The γ′ phases begun to grow at direction of [100] after the specimens aging at 950℃ for 500h and 1050℃ for 100h.The interfacial energy of γ/γ′ phases and the reduction of elastic strain energy was the driving force for γ′ phase′s growth.更多还原