Abstract
Fatigue crack propagation tests were carried out on HT80 steel components on which residual stress fields were induced by electron beam welding, and the influence of residual stress on the fatigue crack opening behavior was investigated. An array of strain gauges attached along the section adjacent and parallel to the section including crack plane was used to examine the variation of stress distribution along the gauges attached section during uploading.
In case of notched status, the variation of stress distribution both in welded and unwelded components subjected tensile load showed same aspects regardless the distribution of residual stress. However, in case that fatigue crack propagated, the variation of stress distribution depended on the distribution of residual stress. Based on the above results, it is clarified that residual stress directly affects the fatigue crack opening behavior.
