时效温度对K77合金组织和性能的影响

Effect of Ageing Temperature on Microstructure and Properties of Superalloy K77

研究了不同时效温度对铸造镍基高温合金 K 77的组织和性能的影响 ,结果表明 ,在三种温度时效过程中 ,均发生不同程度的碳化物反应 ,时效温度越高 ,反应越剧烈 ,生成的 M2 3 C6 颗粒及γ′越多。比较三种时效温度下合金的高温持久性能 ,在 76 0℃时效时 ,持久寿命逐渐降低 ,而在 815℃、 870℃时效时 ,持久寿命有所提高 ,这种现象与 M2 3 C6 及 γ′相的共同强化作用有关。

The effect of ageing temperatures on microstructure and properties of cast Ni- base superalloy K77with optical metalloscope,SEM,EDS and TEM was studied.The results showed that the carbide reaction occurred in different degree at three ageing temperatures and the higer temperature caused the faster reaction so that the quantity of M2 3C6andγ′ increased.The stress- rupture life at 980℃ /1 50 MPa decreaed with increasing aged time at 760℃ ,but that in- creased with increasing aged time at 81 5℃ and 870℃ .The results were related to the coopera- tive strengthening role ofγ′phase and M2 3C6.