Detection Method for Liquid Metal Embrittlement Cracks Inside the Intermediate Sheet Zone of Dissimilar Resistance Spot Welds,Steel Research International

当前位置： X-MOL 学术 › Steel Res. Int. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Detection Method for Liquid Metal Embrittlement Cracks Inside the Intermediate Sheet Zone of Dissimilar Resistance Spot Welds
Steel Research International ( IF 1.9 ) Pub Date : 2020-08-26 , DOI: 10.1002/srin.202000044
Stefan Lindner ₁ , Rüdiger Deike ₂

Affiliation

Liquid metal embrittlement (LME) is a phenomenon where a liquid metal damages a solid bulk metal. Notwithstanding previous investigations, LME remains an actual as well as a still not fully understood topic. A so far not yet investigated area can be defined with ultra‐high strength austenitic stainless steels for passenger cars. The most commonly used joining procedure in car body engineering is still resistance spot welding. During this vehicle assembly step, the uncoated surface of an austenitic stainless steel is because of the process‐related lap joint configuration in direct contact with zinc‐coated surface‐finished steels as a dissimilar material combination. During welding, liquid zinc could penetrate inside the intermediate sheet zone in the grain boundaries of the austenitic steel and is therefore able to initiate cracks in the heat‐affected welding zone. Herein, the radiographic inspection is introduced, which is a process‐reliable, nondestructive detection method for the inaccessible intermediate sheet zone area, which is usable in automotive big‐industrial scale. With the implemented detection method, liquid metal‐induced cracks can be detected in the intermediate sheet zone down to a crack length of 50 μm. Subsequently, the radiographic inspection helps to analyze the crack characteristic depending on surrounding conditions and welding parameters.

中文翻译：

异种电阻点焊中间板区域内液态金属脆化裂纹的检测方法

液态金属脆化（LME）是液态金属损坏固态散装金属的现象。尽管进行了先前的调查，但LME仍然是一个实际的以及尚未完全理解的话题。迄今为止，尚未调查的区域可以定义为乘用车用超高强度奥氏体不锈钢。车身工程中最常用的连接程序仍然是电阻点焊。在该车辆组装步骤中，奥氏体不锈钢的未涂层表面是由于与工艺相关的搭接接头配置，与异种材料组合直接接触镀锌表面处理的钢。焊接时液态锌可能渗入奥氏体钢晶界的中间薄板区域内部，因此能够在热影响焊接区域引发裂纹。本文介绍了射线照相检查，它是一种针对过程中可靠的无损检测方法，适用于无法进入的中间薄片区域区域，该方法可用于汽车大工业规模。使用已实施的检测方法，可以在中间薄板区域中检测出液态金属引起的裂纹，直至裂纹长度为50μm。随后，射线照相检查有助于根据周围条件和焊接参数分析裂纹特征。不可访问的中间薄板区域区域的非破坏性检测方法，可在汽车大工业规模中使用。使用已实施的检测方法，可以在中间薄板区域中检测出液态金属引起的裂纹，直至裂纹长度为50μm。随后，射线照相检查有助于根据周围条件和焊接参数分析裂纹特征。不可访问的中间薄板区域区域的非破坏性检测方法，可在汽车大工业规模中使用。使用已实施的检测方法，可以在中间薄板区域中检测出液态金属引起的裂纹，直至裂纹长度为50μm。随后，射线照相检查有助于根据周围条件和焊接参数分析裂纹特征。

更新日期：2020-11-04

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11