A big thank you to the Fraunhofer Institute for Mechanics of Materials IWM!

Deep rolling for fatigue strength increase or service life extension of cyclically loaded welded structures made of steel and aluminum alloys.

The aim of the investigations proposed here is to prove the fatigue strength increase of welded joints made of normal and high-strength steels and aluminum alloys by deep rolling of the seam transitions and to quantify them in such a way that manageable rules with information on the verification of fatigue strength can be derived for industrial applications. All relevant influences, including the stability of the residual compressive stresses, are to be analyzed comprehensively in order to demonstrate the potential of this process for the post-treatment of welded joints and to be able to define the limits of its use.

Due to the rising prices of raw materials and energy, the economic importance of post-weld treatment processes for increasing the service life of components has increased to a great extent. For the post-treatment of welded joints made of high-strength steels and aluminum alloys, various industrial application areas come into question in which the verification of fatigue strength is decisive for the reliability of parts or components or load-bearing systems. The entire vehicle construction sector is worth mentioning here, where the design of vibration-stressed components has a significant influence on the manufacturing effort, on component and design weight and consequently on manufacturing, operating costs and fuel consumption. This applies to commercial and rail vehicle construction as well as shipbuilding, but also to automotive engineering.

But also in mechanical engineering, crane construction and bridge building, as well as in pressure vessel construction, where welded structures are also exposed to changing stresses, there are requirements comparable to those in vehicle construction. This means that here, too, lightweight designs with high load-bearing capacity and low dead weight are required or made possible, above all through the effective use of high-strength structural materials.

We are pleased to have been able to provide support in this area and wish all those involved all the best for the coming period.