Abstract
Hastelloy XR has been developed in Japan Atomic Energy Research Institute to improve the corrosion resistance of Hastelloy X in VHTR helium environment.
To evaluate weldability of Hastelloy XR, bead welding tests by EB welding and Trans-Varestraint tests by TIG welding were carried out.
The results obtained are as follows.
(1) The weld defects formed in the bead welding test by EB welding were R-porosity and microcracks, both of which are the same as in Hastelloy X.
R-porosity and microcracks can be prevented by using a proper ab value and by controlling the weld heat input, respectively.
(2) In the Trans-Varestraint test by TIG welding, susceptibility to weld cracking was the same for both Hastelloy XR and Hastelloy X. To eliminate microcracking in TIG welding, it is effective to decrease the welding current.
