Ｓ１５ＣＫ同種摩擦圧接継手の延性‐ぜい性遷移挙動

Abstract

In order to make clear the absorption energy, transition temperature and fracture behavior of friction welded joint, the instrumented Charpy impact tests have been carried out at various temperatures from 173K to 473K, using 0.15%C carbon steel specimens with butt joint. The main results obtained are as follows:(1) The energy transition curve of the weld interface and the heat affected zone shifted to the lower temperature side than that of the parent material. The absorption energy at the transition region was the highest at the weld interface.(2) The energy transition temperature was about 250K in both the parent material and the heat affected zone, and apporoximately 230K in the weld interface. These temperatures and the fracture appearance transition temperatures agreed in most cases.(3) The crack propagation energy in the weld interface at the lower position of the transition region was extremely larger in comparison with that of the parent material and the heat affected zone.(4) The impact bending strength of the weld interface, the heat affected zone and the parent material became maximum around the lower position of the transition region, having no corresponding relationship with the absorbed energy.