不同服役温度时间下IC10高温合金组织演变研究

在由于尺寸超差等因素报废的IC10高温合金叶片上进行取样，研究不同服役温度、时间对IC10叶片组织的影响规律以及对显微硬度的影响。结果表明:随热暴露温度和时间的增加，合金中二次γ′相的体积分数逐步降低，在1 120 ℃时，二次γ′相明显球化，体积分数开始显著降低，至1 200 ℃时，短时热暴露（40 h）二次γ′相的体积分数降低至12.96%，说明服役温度、时间对IC10合金的组织有着显著影响；经过热暴露实验后的IC10叶片硬度为HV 354.57～407.28 ，1 050 ℃时，由于基体强度的弱化，试样的硬度低于标准热处理态，随后二次γ′相开始回溶，1 200 ℃之后二次γ′相基本回溶，此时组织为更为均匀细小的三次γ′相，硬度反而升高。

Microstructure Evolution of IC10 Superalloy at Different Service Temperature

The samples used in the present work were taken from the IC10 superalloy blades discarded due to size deviation or other factors. The effects of service temperature and time on microstructure and microhardness of IC10 superalloy were studied. The results show that the volume fraction of the secondary γ′ decreased gradually with the increase of heat exposure temperature and time. At 1 120 ℃, the secondary γ′ phase was obviously spheroidized, and its volume fraction decreased significantly. At 1 200 ℃, the volume fraction decreased to 12.96% after short-term heat exposure (40 h), which indicates that service temperature-time has a significant effect on IC10 microstructure. After thermal exposure, the micro-hardness of IC10 superalloy ranged from HV 354.57 to HV 407.28. At 1 050 ℃, due to strength weakening of the matrix, the hardness of the sample was lower than the standard heat treatment state. Then the secondary γ′ phase began to re-dissolve. The secondary γ' phase’s redissolution basically finished after 1 200 ℃, so that the microstructure was more uniform, composed of fine third-class γ′ phase, and the hardness increased.