1985 年 3 巻 3 号 p. 604-611
The transient thermal stresses of 13 Cr cast steels (SCS5), austenitic stainless steels (SUS304) and their weld metals are investigated by round bar specimens which both ends are fixed and subjected to thermal prestraining cycles simulating weld heat. The experimental results in comparison with SUS304 steels indicate that the effects of transformation expansion on residual stress distributions are remarkable, and the effects of multi-thermal prestraining cycles on residual stress distribution are negligible small in SCS5 cast steels. These results are compared with longitudinal residual stresses of butt welded joints, and it is shown that the both-ends bar testing model is available to simply evaluate residual stress characteristics. It is observed that the residual stress of SCS5 welded joint is about -100 MPa at weld metal and the residual stress of SCS5 welded joint prepared with an austenitic weld metal is about +380 MPa. Three dimensional residual stress distributions of 13 Cr cast steel weldments prepared with an austenitic weld metal are measured by Ueda-Fukuda's method. It is observed that the maximum residual stress is +450 MPa at midthickness, which is nearly equal to 0.2% proof stress of weld metal.