CRYOGENIC PRESSURE VESSELS FORMED FROM LOW-CARBON, HIGH-STRENGTH 9 NICKEL STEELS

摘要

A cryogenic pressure vessel of formed of an ASTM A553 Type 1 cryogenic steel alloy comprising in wt.%: C: 0.01 - 0.04; Mn: up tp 2.0; P: up to 0.02; S: up to 0.15; Si: up to 1.0; Ni: 7 - 11; Cr: up to 1.0; Mo: up to 0.75; V: up to 0.2; Nb: up to 0.1; Al: up to 0.1; and N: up to 0.01. The steel alloy may have an ultimate tensile strength of at least 900 MPa, a total elongation of at least 20%; a microstructure comprised of between 5 and 20 area % reverted austenite and the remainder tempered martensite; a transverse Charpy impact energy of at least 27 J at -196 °C; and a lateral expansion of at least 0.381 mm at -196 °C.