Effects of TIG welding on hydrogen permeation in sus304 stainless steel

Isobe, Kanetsugu; Hayashi, Takumi

Effects of TIG welding, which is one of popular welding methods, on hydrogen isotopes permeation in SUS304 stainless steel were investigated. Tube type of SUS304 stainless steels were used as specimens. One end of the tube was sealed up with a same metal and another end was connected with both a vacuum pumping system and a gas supply system. A tube type of specimen was placed on the vacuum chamber equipped with a quadrupole mass spectrometer (QMS). Deuterium gas was supplied for the inner of tube specimen and the pressure of deuterium gas was kept at 0.2 MPa. Deuterium permeated through specimen was released into the vacuum chamber and was continuously measured with QMS at from 423 K to 673 K. The permeation behavior is found to be almost same over at 623 K, however, TIG welding slightly increased permeation flux at 573 and 523 K.