Aiming at the matter of unqualified ultrasonic inspection results of the forged GH907 alloy ring used for aero engine turbine casing,the influence of the microstructure on the ultrasonic attenuation of the forged alloy ring is quantitatively assessed by means of ultrasonic testing and microstructure obser-vation,and the cause of the bottom wave loss observed in ultrasonic testing is elucidated.The results show that the shape of the large attenuated area in the ultrasonic bottom wave amplitude image was con-sistent with that of the black grain area observed in the macrostructure of GH907 alloy,and the average grain size of the black grain area was larger than that of the non-black grain area,and there were a large number of ε phase with the morphology of Widmannsttten structure.The precipitation of a large number of ε phase can increase ultrasonic attenuation by nearly 40％.It is believed that the forging process should be optimized from the following three aspects:grain refinement,controlling the uniformity of grain size and inhibiting excessive precipitation of ε phase,so that to improve the qualification rate of the forged rings.
关键词
材料检测与分析技术/GH907合金/机匣锻环/超声检测/超声衰减/组织不均匀
Key words
measuring and analysis for materials/GH907 alloy/casing forged ring/ultrasonic testing/non-uniform microstructure
维普
万方数据