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一炉铁路机车用轮箍J307(U)的部分在超声波检测时草状波严重、底波损失大,解剖取样做金相检验,发现超探透声不良区域的实际晶粒度达1级甚至更粗。对该炉轮箍的生产过程调查发现,该炉轮箍晶粒粗大为热处理过程异常所致。对超探透声性能不合格的轮箍进行重新热处理后,绝大部通过了超声波检测,且金相检验正常。在此基础上,对轮箍超探透声检测方法和等温后吊出轮箍的热处理工艺提出了改进意见。
The part of the wheel rim J307 (U) for a railroad locomotive used in the ultrasonic inspection showed that the grass wave was severe and the bottom wave loss was large. Metallographic examination was conducted on the anatomical samples and found that the actual grain size in the ultra sounding and sound imperfection area reached level 1 or even Coarser. The investigation of the production process of the wheel rim found that the coarseness of the wheel rim was caused by the abnormal heat treatment process. The ultra-sound penetration performance unqualified tire re-heat treatment, the vast majority of ultrasonic testing, and the metallographic examination was normal. On this basis, some suggestions are put forward to improve the detection method of the ultra-sounding of the wheel rim and the heat treatment process of hoisting the wheel rim after being isothermal.