Fatigue life of welding joints in carbon-manganese-boron-steel stripsWednesday (08.11.2017) 17:20 - 17:40 Part of:
The fatigue life of a carbon-manganese-boron-steel with an inherent weld seam has been investigated by means of an alternating uni-axial load test. The surface of the steel has been grinded and polished and it has been quenched and tempered after the welding process, so that the material can be considered as homogeneous. However, the results show up that the fatigue lifetime is still strongly influenced by the orientation of the weld seam towards the load direction. Furthermore, fatigue testing of reference specimens without a weld seam reveals that the fatigue lifetime of the weld seam material is significantly below the fatigue lifetime of the reference material.
A fatigue lifetime assessment by use of standard procedures (e.g. FKM) leads to a rather conservative result. Besides quenched and tempered state without additional weld material is not considered in FKM. To avoid that shortcoming, a new correction factor considering the surface and heat treatment is introduced. Comparison of fatigue results and result of the fatigue lifetime assessment by the FKM procedure with and without the correction factor is presented.