长期时效对一种镍基单晶高温合金组织演化及持久性能的影响

研究了长期时效对一种镍基单晶高温合金显微组织及持久性能的影响。结果表明:800℃时效1000h后,γ′相仍保持立方体形态;980℃时效1000h、1010℃时效500h后,γ′相逐渐连接形筏。980℃时效500h、1010℃时效100h后,μ相以针状和颗粒状形态逐渐析出,980℃时随时效时间延长,μ相逐渐增加,1010℃时随时效时间延长,μ相先增加后减少。800℃长期时效后合金的持久寿命变化不大,980,1010℃时随时效温度升高和时效时间延长,合金的持久寿命递减。

Effect of Long-Term Aging on Microstructure Evolution and Stress Rupture Properties of Ni-Based Single Crystal Superalloy

The effect of long-term aging on microstructure and creep properties of a single crystal Ni-based superalloy was investigated. The results show that the phase remains cubic distribution after aging at 800 ℃ for 1000 h; the phase gradually connects and rafts after aging at 980 ℃ for 1000 h or at 1010 ℃ for 500 h. The μ phase precipitates in the form of needles and granules when aged at 980 ℃ for more than 500 h or at 1010 ℃ for more than 100 h; the μ phase gradually increases with the aging time prolonging at 980 ℃, while it first increases and then decreases when aged at 1010 ℃. The creep lives of the alloy change a little after long-term aging at 800 ℃, while the lives decrease with increasing of aging time and temperatures at 980 and 1010 ℃.