PRODUCTION OF CR-MO STEEL FOR PRESSURE VESSEL

摘要

PURPOSE: To easily produce a Cr-Mo steel for pressure vessel having high strength and high toughness and excellent in hydrogen attack resistance. ;CONSTITUTION: A steel stock which has a composition containing, by weight, 0.05-0.20% C, ≥0.40% Si, 0.1-1.0% Mn, ≤0.5% in total, of Cu and/or Ni, 2.0-3.5% Cr, 0.8-1.6& Mo, 0.10-0.40% V, 0.005-0.1% Nb, ≤0.08% Al, ≤0.010% P, ≤0.004% S, and ≤0.006% N and also containing, as selective components, one or ≥2 kinds among 0.005-0.035% Ti, 0.0005-0.004% B, ≤0.03% Ca, and ≤0.03% REM is subjected to light draft rolling at 5-20% draft at a temp. between 900°C and the Ar₃ and then to direct hardening, by which the Cr-Mo steel for pressure vessel can be produced.;COPYRIGHT: (C)1993,JPO&Japio