Influences on the Fatigue Strength of Laser-Welded High-Purity Copper Connections

Due to their excellent conducting properties, components made of high-purity copper are increasingly being used in the field of electrified applications. In particular for components with welded joints made of high-purity copper, there is still no computational basis for evaluating the fatigue strength of these joints. With the help of extensive fatigue tests, the influence of the local welding geometry and the locally modified microstructure on the fatigue strength of these connections is therefore investigated. In addition, a structured procedure to separate the influences of the local geometry and the local microstructure on the fatigue strength from each other is presented, and the results are shown in a comparative way in one figure. The investigations show that the influence of the local geometry on the fatigue strength is dominant compared to the one of the microstructure. However, consideration of the local geometrical and metallurgical notches is recommended for the future development of a general fatigue life calculation for welded high-purity copper joints.