New Approach for Weldability and Process Robustness Testing for Spot Welding – PROFS

There is a large need for an improved method for evaluation of weldability of resistance spot welded joints and robustness for the process, to decrease the impact of the differences between lab- and production environment, reduce spatter and repair work. It is even more needed when implementing new materials with improved material characteristics, but often reduced in weldability. Modern weld control systems increase the possibilities for feedback and adaptive control of parameters, which is not considered in the evaluation methods today. A new evaluation method incorporating these aspects will enable a safe and efficient use of more advanced high-strength materials, with reduced component weight, increased productivity and decreased environmental impact. This pre-study will investigate factors (process-, equipment- and material related) with largest impact on process robustness and transferability. The results will be used for development of a new, improved methodology for resistance spot weldability evaluation, including the most critical factors occurring in production. Subsequently, this will increase the process robustness of future welds. The development of such a model requires a thorough investigation of how different factors affect the weld quality in resistance spot welds, and how these factors differ between process planning laboratories and production, and also between different stations in production. This investigation will be performed through collection of data from weldability tests and production, and from verifying experiments. The project will expand the usability and robustness of equipment existing in manufacturing industry today, which will enable fast implementation of the developed method.