Increasing Competitiveness in Structural Assembly by using Solid-State Spot Welding (Friction Spot Welding and Friction Stir Spot Welding) as a Replacement of Traditional Fasteners and Rivets?

摘要

To join sheet metal made out of aluminium, riveting is common practice. This process contains several disadvantages. On the one hand, large, specially designed and cost-intensive machines are used within automation engineering. Normally, those tools are not reconfigurable and cannot be used for general purposes. On the other hand, adding the rivet to the structure also increases weight of the whole craft. The proposed method of friction welding addresses those limitations of riveting. At the Institute of Production Engineering, Helmut-Schmidt-University, research is conducted to provide a control assuring process reliability to perform friction welding fully automated as well as manually. Friction spot welding is a sub-section of friction welding, where a rotating tool that consists out of three parts is used to heat up material to a dough-like state. Since friction spot welding produces selective dot-shaped connections of overlapping materials, the production requirements are similar to riveting or resistance spot welding. In contrast to other bonding techniques, friction spot welding can be integrated within the production process without major interferences or changes. Another advantage of friction spot welding is the simple process operation. Friction spot welding only requires one operation. Processing time and expenses are therefore reduced.