34CrMo1A钢转子在制造过程中经超声波探伤发现内部有缺陷,采用宏观检验、金相检验、化学成分分析及断口分析等方法,对转子内部缺陷的类型进行了分析。结果表明:转子内部缺陷性质为白点,其微观断口形貌呈现典型的四周放射状条纹的白点特征,且伴有氧化铝类夹杂物。该批转子氢含量偏高是产生白点缺陷的主要原因。

The internal defects were found by ultrasonic testing in manufacturing process of 34CrMo1A rotor. The internal flaw type of rotor was analyzed by means of macroscopic examination, metallographic examination, chemical composition analysis, fracture analysis and so on. The results showed that the type of internal defects was flake, whose micro fractography showed as radial stripes typical characteristics of flake, and alumina inclusions were also found in the rotor. The high content of residual hydrogen in rotor was the main reason of flake defect.