摘要
17-4PH钢涡轮轴经固溶时效处理、机械加工成型和镀硬铬工艺后的磁粉探伤检测时发现其端面有荧光磁粉显示存在缺陷,采用化学成分分析、显微组织和断口形貌观察、硬度和残余应力测试、磁粉探伤检测等方法,结合工艺生产过程的排查结果,对缺陷性质及产生原因进行了诊断,通过工艺试验研究确定工艺改进方案。结果表明,17-4PH钢涡轮轴端面荧光磁粉显示的缺陷是微裂纹,该裂纹是在镀铬工序中产生的氢脆裂纹。涡轮轴硬度偏高,残余应力偏大是产生氢脆裂纹的主要原因。采用430℃保温1 h的欠时效处理工艺方案可以适当的降低17-4PH钢涡轮轴的硬度和残余应力,避免其端面氢脆裂纹的产生。
Defects were found at the end face of 17-4PH steel turbo shaft after solution and aging treatment,machining forming and hard chrome plating by using magnetic particle indication,and the characteristics and causes of which were analyzed by means of chemical composition analysis,microstructure and fracture morphologies observation,hardness and residual stress testing,magnetic particle indication,and diagnosed by combining with the inspection results of the production process.The results show that the defects are hydrogen embrittlement microcracks occurred during the hard chrome plating process,and the causes of which are mainly the higher hardness and the higher residual stress of the 17-4PH steel turbo shaft.Using underaging treatment at 430℃for 1 h can appropriately reduce the hardness and residual stress of the 17-4PH steel turbo shaft,and avoid the generation of hydrogen embrittlement cracks on the end face.
作者
刘松
韩艳春
Liu Song;Han Yanchun(AVIC Jincheng Nanjing Electrical and Hydraulic Engineering Research Center,Nanjing Jiangsu 211106,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2021年第10期252-256,共5页
Heat Treatment of Metals
关键词
17-4PH钢
涡轮轴
氢脆裂纹
残余应力
磁粉显示
17-4PH steel
turbo shaft
hydrogen embrittlement crack
residual stress
magnetic particle indication
