Effect of chemical composition on corrosion properties of austenitic weld metal

Tokita, Shun*; Kadoi, Kota*; Aoki, So  ; Inoue, Hiroshige*

In this study, the objective was to estimate microstructure and corrosion resistance of weld metals of austenitic stainless steels to obtain characteristics of the weld metals and fundamental knowledge for improvement of its reliability. Electrochemical potentiokinetic reactivation (EPR) test and pitting potential measurement were carried out to estimate the corrosion resistance. In the EPR test, improvement of corrosion resistance at grain boundaries was confirmed in weld metal which included more Cr and Mo. On the other hand, Ni contents did not affect to EPR values. Etching microstructure along dendritic cell was observed in every EPR test. Weld metals which have a higher pitting index showed a higher pitting potential.