In fabricating nuclear power plant components resultant safety is of most importance, and it is desirable to use highly reliable welding methods.
The authors studied the electron beam weldability of austenitic stainless steel from the viewpoint of joint properties of welded joints and the welding practice. The results obtained are summarized as follows:
(1) Basic welded joint properties are good but the tensile strength of welded joint is slightly lower than that of the base metal.
(2) The high cycle fatigue strength of welded joint without reinforcement is similar to that of the base metal. The fatigue strength of welded joint with reinforcement, however, is lower than that of base metal with the fatigue strength reduction coefficient of 1.6 to 1.8 at 105 to 106 cycles.
(3) The groove gap of up to 0.4 mm at plate thickness of 20 mm, up to 0.5 mm at plate thickness of 50 mm, and up to 0.6 mm at plate thickness of 80 mm enabled welding to be carried out without concavities forming.
(4) The treatment of start and end is performed with no problems and the discharge holes can be repaired by applying electron beam welding several times.
