Mechanical properties of cryogenic high manganese steel joints filled with nickel-based materials by SMAW and SAW

Low temperature high manganese austenite steel is expected to replace the 9Ni steel and be widely used in the manufacturing of liquefied natural gas (LNG) storage tanks due to its excellent low temperature mechanical properties and good economic advantages. As a new material, few welding materials match it. In this paper, a kind of new cryogenic high manganese steel was welded with nickel-based welding materials by shielded metal arc welding (SMAW) and submerged arc welding (SAW). The microstructures were both austenite in joints, which could lead to good mechanical properties at low temperatures. The comprehensive properties of SMAW joints are better than those of SAW joints. In this way, the ultimate tensile strength (UTS) and elongation were 773 MPa and 30% at 298 K while the UTS and elongation of SAW joints were 713 MPa and 24%. SMAW joints also showed good bending properties. Especially at 77 K, the average impact energy was higher than that of SAW joints.

Automated summary

The new cryogenic high manganese steel can achieve good mechanical properties through different welding methods, with the comprehensive performance of arc welding joints better than submerged arc welding joints.