热等静压温度对FGH95合金组织和持久性能的影响

Effects of hot isostatic pressing temperature on microstructure and stress rupture properties of FGH95 superalloy

通过对FGH95合金进行不同温度的热等静压处理、组织形貌观察及持久性能测试,研究热等静压温度对合金组织结构与持久性能的影响。结果表明:在低于γ′相溶解温度进行热等静压时,粗大γ′相沿颗粒边界区域不连续分布;随热等静压温度的升高,合金中一次粗大γ′相的数量、尺寸逐渐减小,经1 140℃固溶处理后,晶粒尺寸无明显变化;合金经1 180℃热等静压及完全热处理后,粗大γ′相完全溶解及γ′相贫化区消失,晶粒尺寸明显长大,γ′相和细小碳化物沿晶界及晶内弥散析出,因而合金具有较好的持久性能;合金在持久性能测试期间的变形机制是位错在基体中滑移及剪切γ′相。

By means of the hot isostatic pressing treatment（HIP） at the different temperatures,microstructure observation and stress rupture properties measurement,the influence of HIP temperatures on the microstructure and enduring properties of FGH95 nickel-base superalloy were investigated.The results show that,when the HIP temperature is lower than γ′ phase dissolving temperature,coarser γ′ phase discontinuously distributes in the particle boundary regions and the quantity and size of coarser γ′ precipitates decrease gradually as the HIP temperature increasing.No feature of the grain growing up is detected after the alloy is solution treated at 1 140 ℃,and the carbide particles distribute along the grain boundary and in the grain.After HIP-treated at 1 180 ℃ and fully heat treated,the coarser γ′ phase in the alloy is dissolved,the depleted zone of the fine γ′ phase disappears,and the grain size in the alloy obviously increases,and the γ′ phase and fine carbide are dispersedly precipitated within the grains and boundaries,which enhances the enduring properties of the alloy.The deformation mechanisms of the alloy during endurance properties testing are that the dislocations slip in the matrix or shear into γ′ phase.