Microstructure and Mechanical Properties of Cryogenic High-Manganese Steel Weld Metal

Extant studies have focused on the development of high-manganese austenitic steel, which is a potential cost-effective alternative to commercial cryogenic materials such as 9% Ni steels, 304 stainless steels, and Al5083 alloys. The development of suitable welding consumables is of significant importance in the commercial application of this new material for cryogenic applications. Specifically, flux-cored arc welding consumables that allow all-positional welding for high-Mn steel are required to fabricate liquefied natural gas (LNG) tanks. Hence, a welding wire alloyed with austenite-stabilizing elements (e.g., C, Mn, and Ni) was developed for cryogenic toughness. The microstructure and mechanical properties were evaluated as a function of the alloy composition. This unique combination of strength and toughness demonstrated the potential of this newly developed high-Mn steel for cryogenic services.