Microstructural and Mechanical Properties of 9%Ni Steels Used for the Construction of LNG Storage Tanks

Abstract

The growing needs for energy combined with the will to reduce CO2 emissions lead to the increase of the demand for liquefied natural gas (LNG), which will be stably available for many decades to come. Cryogenic materials used for the manufacture of the inner tanks for LNG storage are composed of 9% Ni steel plates with excellent low-temperature toughness, great ductility and crack resistance for a high safety level. To guarantee the reliability and safe operation of large-scale metallic structures exposed to cryogenic temperatures for extended periods, it is important to evaluate structural and mechanical properties of the metal base as well as the welded zone in their own operating conditions in order to prevent damages that could occur.