摘要
利用超声波检测、低倍检验、金相显微镜、拉伸试验机及扫描电镜对锻造厂的F65锻造方坯和轮毂锻件的裂纹成因进行宏观及显微组织分析,为深海采油高压传输管法兰的缺陷特征的研究提供可行的方法。结果表明:裂纹是组织残余应力所致,裂纹成因与材料冶金缺陷及氢致裂纹无关,裂纹主要沿条带组织中的贝氏体呈穿晶扩展,与粗大不均匀的铁素体与贝氏体交替分布的带状显微组织有关。锻件的组织应力与锻坯对角线锻造残余剪切应力叠加为裂纹提供了外在条件,其显微组织粗大不均匀是产生裂纹的内在原因。
The macroscopical and microscopic structures on F65 forging billet and hub forging were analyzed by means of ultrasonic testing,microstructure inspection,metallographic microscope,tensile testing machine and scanning electron microscope to discuss the causes of cracking,which provided a feasible method for the research of defect characteristics of high-pressure transmission pipe flange in deep-sea oil production. The results showed that the cracking was caused by the residual stress of the structure. The cause of the crack was not related to the metallurgical defects and hydrogen-induced cracks of the material. The cracks were mainly propagated along the bainite in the strip structure,which was related to the strip microstructure with alternating distribution of coarse and uneven ferrite and bainite. The superposition of the structural stress of forgings and the residual shear stress of diagonal forging provided the external conditions for the cracks. The internal cause of the cracks was the uneven microstructure.
作者
陈新华
汪海潮
陈昌华
张思瑞
吴永胜
CHEN Xinhua;WANG Haichao;CHEN Changhua;ZHANG Sirui;WU Yongsheng(Technology Center,Nanjing Develop Advanced Manufacturing Co.,Ltd.,Nanjing 210048,China)
出处
《物理测试》
CAS
2021年第1期50-55,共6页
Physics Examination and Testing
关键词
F65材料
深海油气
检验
裂纹
应力
宏观特征
显微组织
F65 material
deep sea oil and gas
inspection
crack
stress
macroscopic characteristics
microstructure
