텅스텐아크용접에 의한 Zirconium의 동종 및 이종용접 특성 분석

Zirconium has excellent mechanical strength and high heat resistance and excellent corrosion resistance, and it is very important to study zirconium''s dissimilar welding properties since it can be used in various applications under harsh environments. Similar welding of pure zirconium and dissimilar metal welding of pure zirconium and pure titanium were performed by TIG welding, and the welding properties were studied in association with microstructural and mechanical properties. In the Zr/Zr welded specimen, sound FZ and HAZ regions showed a basketweave microstructure composed of plate α phase. FZ region of Zr/Ti dissimilar welded specimen exhibited a maximum hardness value of 354.8 Hv, which is about three times higher than that of Ti base metal, due to the precipitation of very fine metastable ω and α phases in the beta matrix. In addition, due to the microstructural continuity in the FZ and HAZ regions, excellent elongation property of 21% was exhibited. (Received June 3, 2021; Revised June 18, 2021; Accepted June 22, 2021)