GH4169合金环锻件残余应力超声检测

GH4169合金环锻件在新型航空和航天发动机中起着重要作用,残余应力对机械制造过程有着重要的影响。对GH4169制压气机四级盘的整体应力分布进行了超声临界折射纵波(longitudinal critical refracted wave,LCR波)测量,并将该应力分布情况与仿真模拟应力结构图进行对比,结果基本一致,验证了超声LCR波应力检测的准确性。结论表示该类环锻件模锻后存在较大的周向拉应力,该应力的存在会导致该零件的疲劳强度大幅度降低,使用寿命大幅度减少。针对该类问题,通过超声LCR波测量该GH4169制压气机盘喷丸前后应力的变化,试验结果可知,喷丸强化会重塑GH4169环锻件残余应力场,降低其周向拉应力,其行为会有效提高该零件的疲劳强度和使用寿命。超声检测结果误差在10%以内,验证了GH4169环锻件超声LCR波法检测的实用性与可靠性。

Ultrasonic Testing of Residual Stress in GH4169 Alloy Ring Forgings

GH4169 alloy ring forgings play an important role in new aerospace and aerospace engines, and residual stresses have an important impact on the mechanical manufacturing process. Ultrasonic LCR wave measurement was carried out on the overall stress distribution of the GH4169 compressor four-stage disc, and the stress distribution was compared with the simulated stress structure diagram. The results were basically consistent, and the accuracy of ultrasonic LCR wave stress detection was verified. The conclusion indicates that there is a large circumferential tensile stress after forging of this type of ring forging, and the existence of this stress will cause the fatigue strength of the part to be greatly reduced and the service life to be greatly reduced. For this kind of problem, the change of stress before and after shot peening of the GH4169 compressor is measured by ultrasonic LCR wave. The test results show that the shot peening will reshape the residual stress field of GH4169 ring forging and reduce its circumferential tensile stress. Effectively improve the fatigue strength and service life of the part. The error of ultrasonic testing results is less than 10%, which verifies the practicability and reliability of ultrasonic LCR wave detection of GH4169 ring forgings.