9% Ni steel is a W (Ni)-9% low-alloy high-strength steel plate
developed in 1944. It was developed by the International Nickel Company's product research laboratory. It is a low-carbon quenched and tempered steel organized by Markov. Body plus bainite. This kind of steel has good toughness and high strength at very low temperature
, and has a small coefficient of thermal expansion compared with austenitic stainless steel and aluminum alloy, and has good economical efficiency. The use temperature is as low as 196 ° C, and it has passed since 1960. Studies have shown that 9% Ni steel has become one of the main materials used in the manufacture of large LNG storage tanks since it has been safely used without post-weld stress relief heat treatment.
The main features of steel are high nickel content, high purity, high strength, high low temperature impact toughness and good weldability. Through research and development, steel can achieve the following performance indicators: 9% Ni steel: ReH ≥ 585MPa, Rm = 680 ~ 820MPa, A ≥ 18%, -196 ° C, AKv (T) ≥ 150J, AKv (T) ≥ 80J (EU standard ).