PRESSURE VESSEL STEEL WITH EXCELLENT LOW TEMPERATURE TOUGHNESS AND SULFIDE STRESS CORROSION CRACKING, MANUFACTURING METHOD THEREOF AND MANUFACTURING METHOD OF DEEP DRAWING ARTICLE

摘要

The present invention relates to steel for a low temperature and high pressure vessel. More specifically, the present invention relates to steel for a high pressure vessel having low temperature toughness and sulfide stress corrosion cracking (SSCC), a manufacturing method thereof, and a manufacturing method of a deep drawing article. To achieve this, the steel for a high pressure vessel having low temperature toughness and SSCC comprises: 0.3-0.4 wt% of C, 0.15-0.40 wt% of Si, 0.4-1.0 wt% of Mn, 0.001-0.05 wt% of Al, 0.8-1.2 wt% of Cr, 0.15-0.80 wt% of Mo, less than or equal to 0.1 wt% of Ni, 0.0005-0.0020 wt% of Ca, less than or equal to 0.015 wt% of P, less than or equal to 0.015 wt% of S, and a remaining amount of Fe and impurities. A fine structure is composed of a three-phase composite structure of ferrite, bainite, and martensite.