金属热处理 ›› 2021, Vol. 46 ›› Issue (3): 218-222.DOI: 10.13251/j.issn.0254-6051.2021.03.042

• 测试与分析 • 上一篇    下一篇

不锈钢拉杆接头断裂失效分析

李家华1, 李萍2, 孙松3, 谢辉3, 曾茵3   

  1. 1.贵州省分析测试研究院, 贵州 贵阳 550014;
    2.浙江大学 城市学院, 浙江 杭州 310015;
    3.贵州省检测技术研究应用中心, 贵州 贵阳 550014
  • 收稿日期:2020-10-17 出版日期:2021-03-25 发布日期:2021-05-08
  • 通讯作者: 曾茵,工程师,E-mail:371941808@qq.com
  • 作者简介:李家华(1968—),男,高级工程师,主要研究方向为冶金、材料分析,E-mail:ljh681208@126.com。
  • 基金资助:
    贵州科学院青年基金(黔科院字[2018]01号)

Fracture failure analysis of stainless steel tie rod joint

Li Jiahua1, Li Ping2, Sun Song3, Xie Hui3, Zeng Yin3   

  1. 1. Guizhou Academy of Testing and Analysis, Guiyang Guizhou 550014, China;
    2. Zhejiang University City College, Hangzhou Zhejiang 310015, China;
    3. Guizhou Research and Application Center of Testing Technology, Guiyang Guizhou 550014, China
  • Received:2020-10-17 Online:2021-03-25 Published:2021-05-08

摘要: 某桥梁工程用不锈钢05Cr17Ni4Cu4Nb拉杆OU型接头服役过程中O型孔处发生断裂,为查明失效原因对其化学成分、宏观断口、显微组织、力学性能等方面进行了检测和分析。结果表明:接头化学成分与GB/T 1220—2007中05Cr17Ni4Cu4Nb牌号标准相符,规定塑性延伸强度、抗拉强度与该牌号钢480 ℃下时效处理的标准相符,但断后伸长率和断面收缩率低于标准要求,材料塑性较差,分析其原因主要是热处理时固溶温度偏高,δ铁素体析出致材料偏脆,零件表面缺口敏感性高,导致发生过载脆性断裂。

关键词: 不锈钢, 拉杆, 接头, 断裂, 失效分析

Abstract: The O-shaped hole of the stainless steel 05Cr17Ni4Cu4Nb tie rod OU type joint used in a bridge project was broken during service. In order to find out the cause of the failure, the chemical composition, macroscopic fracture, microstructure, and mechanical properties were tested and analyzed. The results show that the chemical composition of the joint is in accordance with the standard of 05Cr17Ni4Cu4Nb in GB/T 1220—2007, the specified non-proportional elongation strength and tensile strength reaches the technical requirement of the steel aged at 480 ℃. However, the elongation after break and percentage reduction of area are lower than the requirements, revealing that the material is with poor plasticity, which should be due to the precipitated δ ferrite resulted from a high solution treatment temperature. Therefore, the overload brittle fracture of the joint occurs which is caused by its high surface notch sensitivity.

Key words: stainless steel, tie rod, joint, fracture, failure analysis

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