This paper reports on a long term research effort to develop an improved filler metal for gastungsten-
arc welding (GTAW) of Alloy 690. The goal of this work was to maintain the corrosion
resistance of wrought Alloy 690 while eliminating ductility dip cracking (DDC) or other as-welded
defects in prototypical welds. Three candidate alloys of 24 wt.%, 27 wt.%, and 30 wt.%
chromium have been evaluated for their stress corrosion cracking (SCC) resistance, weldability,
mechanical properties, and phase stability. These alloys are compositionally similar to the Alloy
600 filler metal EN82 with high amounts of chromium. Results of testing to date show that these
chromium additions significantly enhance the SCC resistance over EN82 while maintaining the
weldability, mechanical properties, and phase stability of Alloy 600 filler metal. Results from
weld mockups, weldability testing, microstructural and microchemical characterization, and
computational modeling also show that DDC is a form of precipitation-induced-cracking and that
it can be effectively mitigated via alloying to control the type and extent of carbide formation.