Composition Design and Heat Treatment Welding Process Analysis of High‑manganese Austenitic Cryogenic Steel

A new type of Ni-free cryogenic steel has been developed by replacing the more expensive Ni with low-cost Mn， which has become a new hot spot in the current research of steel for liquefied natural gas （LNG） storage tanks. The concept and characteristics of cryogenic steel are introduced in the beginning and then the research of high manganese austenitic cryogenic steel at home and abroad are introduced in this paper. In addition， the requirements on composition and properties of high manganese austenitic cryogenic steel in national and group standards are listed in detail. By comprehensive analysing the effects of different elements on the mechanical properties of high manganese austenitic cryogenic steel， it is concluded that Fe-24Mn-0.45C-3Cr-0.5Cu series high manganese austenitic cryogenic steel has excellent comprehensive properties， and can be used as a reference for the optimization of composition of high manganese austenitic cryogenic steel design. For the welding process， heat treatment can effectivel