Effect of metallurgical evolution during post-weld aging treatment on localised corrosion of resistance spot welding joints of A286 superalloy

Abstract

The combined effect of resistance spot welding and precipitation hardening on the localized corrosion of A286 superalloy is studied. The specimens tested by DLEPR were welded in the solution treated condition, and then subjected to different precipitation hardening treatments. For both base metal and weld nugget, the maximum localized corrosion is reached when η phase is clearly observable. The fact that the localized corrosion resistance of weld nugget is different from that shown by base metal may be explained by the segregation of Ni and Ti towards the interdendritic region of weld nugget (studied by using SEM/EDX analysis).