Evaluation of Different Filler Metals on Welding Super Austenitic Sanicro 35® (UNS N08935) Grade for Refineries, Chemical and Petrochemical Industries

Abstract Alloy 35Mo (UNS N08935) is a super-austenitic alloy with excellent corrosion resistance in high chloride applications or acidic environments with halide contaminants. It is a cost-efficient alternative to nickel-based alloy 625 for refineries, petrochemical and chemical plants, and renewable energy applications where duplex stainless steel is no longer an option. The welding process is crucial for fabrication, particularly when selecting filler metal. However, certain filler metals may be challenging to acquire or have extended delivery times. The goal of this study is to assess the mechanical properties and corrosion resistance of alloy 35Mo weld joints using three different filler metal alloys: ERNiCrMo-13, ERNiCrMo-4, and ERNiCrMo-10, along with Gas Tungsten Arc Welding (GTAW) as the welding method. This study is a continuation of the previous paper, C2024-20854. The welds were evaluated according to EN ISO 15614-1:2017 (tensile, bending, and hardness), and the microstructure of the weldments was examined. Additionally, pitting corrosion and chloride stress corrosion cracking (ClSCC) were evaluated using ASTM G48 Method C and ASTM G123.