摘要
42CrMo钢六角头螺栓在热镀锌工艺完成后的磁粉探伤时发现部分螺栓的圆角处存在裂纹。采用光学显微镜、扫描电镜和能谱仪等对螺栓进行了断口、显微组织和成分分析。结果表明,开裂螺栓经破断后的断口符合氢脆断口特征,断口附近氢元素的质量分数偏高,达4×10^(-6)。裂纹形貌特征和氢脆裂纹特征吻合,裂纹两侧组织为正常的调质组织且裂纹内还发现有锌液残余,可以排除裂纹是由于组织异常或在淬火时产生的。因此,可以推断42CrMo钢六角头螺栓开裂类型为氢致开裂,氢致开裂发生在热镀锌过程中。
Cracks were found at the round corners of the 42CrMo steel hexagon head bolts after hot dip galvanizing through magnetic particle inspection. Fracture, microstructure and composition analysis of the cracked bolt were carried out by means of optical microscope, SEM and EDS. The results show that the fracture of the cracked bolts conforms to the characteristics of hydrogen embrittlement, and the mass fraction of hydrogen near the fracture is as high as 4×10^(-6).The crack characteristics are consistent with the hydrogen embrittlement crack characteristics. The microstructure on both sides of the crack is normal quenched and tempered structure and zinc residue is found in the crack, which can exclude that the crack is caused by abnormal tissue or quenching. Therefore, it can be reasonably inferred that the crack of 42CrMo steel hexagonal bolt is hydrogen-induced cracking, which occurs in the process of hot dip galvanizing.
作者
赵全育
梁嘉俊
陈旭鹏
童波
夏国华
严琴
丁志敏
Zhao Quanyu;Liang Jiajun;Chen Xupeng;Tong Bo;Xia Guohua;Yan Qin;Ding Zhimin(Finework New Energy Technology Co.,Ltd.,Changde Hunan 415701,China;School of Materials Science and Engineering,Central South University,Changsha Hunan 410083,China)
出处
《金属热处理》
CAS
CSCD
北大核心
2023年第1期257-260,共4页
Heat Treatment of Metals
关键词
42CRMO钢
六角头螺栓
热镀锌
氢致开裂
42CrMo steel
hexagon bolts
hot dip galvanizing
hydrogen induced cracking
作者简介
赵全育(1983—),男,工程师,主要研究方向为风电紧固件材料,E-mail:fwyoujun2020@126.com;通讯作者:梁嘉俊,硕士研究生,主要研究方向为先进钢铁材料,E-mail:1270080863@qq.com。
