Influence of Hydrogen for Crack Formation during Mechanical Clinching
Influence of Hydrogen for Crack Formation during Mechanical Clinching
复制标题
机械铆接过程中氢气对裂纹形成的影响
DOI：
10.1016/j.prostr.2018.12.187
复制
发表时间：
2018
期刊：
影响因子：
--
通讯作者：
Toru Kato
中科院分区：
文献类型：
--
作者：
D. Sasaki;Yuki Tampa;Toru Kato
在酸洗过程中，氢进入钢中，促进裂纹的形成，酸洗是连接前的预处理过程。机械夹紧是汽车工业中常用的一种连接方法，在机械夹紧过程中，有时会由于应变过大而产生裂纹。为了保证接头的可靠性，弄清氢对接头裂纹形成的影响是十分重要的。在本研究中，我们阐明了氢对裂纹形成对机械粘接的影响。氢电荷是用电解阴极电荷进行的。装药后进行机械夹持。对钢板和铝合金板进行机械夹持。为了明确氢的影响，在没有氢炭化的情况下进行了机械粘接。为了研究裂纹的形成，对试件进行了切割并观察了切割表面。通过光学显微镜和电子显微镜观察夹紧过程中接头断裂的断裂面。由载荷-位移图可知，未充氢时，压缩载荷随位移的增加而增加。另一方面，随着充氢量的增加，压缩载荷暂时减小，表明此时形成了裂纹。切割表面观察表明，在低充氢和无充氢两种情况下均形成了互锁。当充氢量较低时，接头未形成裂纹。高充氢时，在连接点处形成裂纹。断裂分析显示断口呈脆性样。结果表明，在机械夹持过程中，氢诱导裂纹形成。
Hydrogen intrudes into the steel during pickling process which is a pre-processing before a joining process, promoting crack formation. In a mechanical clinching which is one of joining method in the automotive industry, cracks due to large strain sometimes forms. In order to guarantee reliability, it is important to clarify the influence of hydrogen on crack formation of the joint. In this study, we clarified the influence of hydrogen for the crack formation on the mechanical clinching. Hydrogen charge was carried out using an electrolytic cathode charge. After the charging, mechanical clinching was performed. Mechanical clinching was carried out with steel plate and aluminium alloy plate. To clarify the influence of hydrogen, mechanical clinching was conducted without hydrogen charring. To investigate the crack formation, the test piece was cut and the cut surface was observed. When the joint was broken during the clinching, the fracture surface was observed using an optical microscope and an electron microscope. The load-displacement diagram showed that without hydrogen charging, the compressive load increased as the displacement increased. On the other hand, the compressive load temporarily decreased with high hydrogen charging, suggesting that cracks formed at the time. The cut surface observation showed that interlock was formed in both cases with low hydrogen charging and without hydrogen charging. With low hydrogen charging, no cracks were formed in the joint. When high hydrogen charging was performed, cracks were formed at the joining point. Fracture analysis showed brittle-like fracture surface. These results indicate that hydrogen induces crack formation in the mechanical clinching.
具有局部特征向量的大型内部全纯扩展图
DOI：
--
发表时间：
2021
期刊：
影响因子：
--
作者：
Kagawa Kotaro;Takimoto Gaku;Seehausen Ole;Sefan Asamitsu;Miyu Suzuki;佐竹 翔平
通讯作者：
佐竹 翔平