Weldability of dissimilar joint between PNC-FMS and Type 316 steel under electron beam welding

電子ビーム溶接を用いたPNC-FMSとSUS316鋼の異材溶接性について

矢野 康英  ; 皆藤 威二 ; 丹野 敬嗣  ; 大塚 智史   

Yano, Yasuhide; Kaito, Takeji; Tanno, Takashi; Otsuka, Satoshi

電子ビーム溶接を用いたPNC-FMSとSUS316鋼の異材接合を実施し、電子ビーム条件と溶接後熱処理条件(PWHT)の最適化を実施した。最適な電子ビーム条件は、焦点距離30-40mmで、溶接速度1750-2000mm/minであり、最適なPWHTは690C60minであった。結果として、溶融線近傍にデルタフェライトの形成がなく、母材と同等な強度を有する接合を実施することができた。電子ビーム溶接は、PNC-FMSとSUS316鋼の異材接合に対して有望な溶接方法であることが分かった。

The dissimilar butt welding joint of 11Cr-ferritic/martensitic steel (PNC-FMS) and Type 316 austenitic steel (SUS316) produced by electron beam (EB) welding was studied. This study was carried out to investigate optimization of EB welding and post weld heat treatment (PWHT). Optimum EB welding conditions were a focus position of 30-40 mm and a welding speed of 1750-2000 mm/min, and optimum PWHT was performed after welding at 690C for 60 min. As a result, no formation of delta ferrite was observed adjacent to the fusion zone, and the mechanical properties of the welds were similar to those of the base material. In this regard, EB welding is a proper fusion welding process for dissimilar PNC-FMS and SUS316.