Expulsion In Resistance Spot Welding

Spot welding consists of making a lapped assembly with one or two joins and one or several spot welds. The spot weld is a small pool of molten metal which solidifies forming a join between the parts of a lapped assembly. Resistance spot welding is commonly used in the automotive industry, because it has the advantage which is high speed, high-production assembly lines and suitability for automation. Although this process seems quite simple, it is actually a very complex system which is affected by a lot of variable. A common phenomenon in resistance spot welding (RSW) is expulsion, the ejection of molten metal during welding. Expulsion, which can be observed frequently during spot welding, happens at either the faying surface or the electrode/work piece interfaces. In this book, a systematic approach was taken to: understand the fundamental of resistance spot welding (by means of metallurgy and electromechanical behavior) and then a literature research for eliminating expulsion and finally an application in industry with practical approach.