Abstract
For the application of electron beam welding to nuclear and thermal power plant, electron beam weldability of carbon steel (SGV49, SB49) and Cr-Mo low alloy steel (SCMV3A) have been investigated. The results obtained are summarized as follows;
(1) Tensile strength and 0.2% proof stress of the welded joint at room temperature and high temperature up to 350°C satisfy the base metal code and the MITI code. Test specimens fractured in the base metal.
(2) Tensile properties of carbon steel weld metal are also good.
(3) Reference nil ductility temperature (RTND-r) of weld metal in SGV49 steel is -30°C as derived from Charpy V-notch tests and drop weight tests.
(4) The high cycle fatigue strength of the welded joint without reinforcement is similar to that of the base metal. The fatigue strength of the joint with reinforcement is lower than that of the base metal, and its fatigue strength reduction coefficient is 1.07 to 1.31 at 105 to 2×106 cycles.
