The presented work deals with the evaluation of fatigue life of non-welded as well as laser welded high strength steel WELDOX 960 in the area of low cycle fatigue. The theoretical part describes the effect of fatigue on the material and possibilities of improving fatigue properties. It also deals with the characterization of high strength steels, their weldability and fatigue resistance of the material. The experimental part presents the results of static, fatigue tests and FEM analyzes for both basic and laser welded materials. As a results are Wöhler's diagrams comparing the life of the base material and the material containing the welded joint. Computer software using the FEM principle was used for their creation.

Acknowledgements: This work was supported by the Slovak Research and Development Agency under the contract No. APVV-14-0096.