STEEL MATERIAL WITH EXCELLENT CORROSION RESISTANCE FOR TANK UPPER DECK OF CRUDE OIL TANKER OR FOR HOLD OF BULK CARRIER

摘要

PURPOSE: A steel material for the upper deck of an oil tanker or the cargo hold of a bulk carrier is provided to secure an excellent corrosion resistance by being equipped with a steel material satisfying a component formation of regarding rules and to be used for the area exposed to a severe corrosion environment in which a sulfur containing material exists. CONSTITUTION: A steel material for the upper deck of an oil tanker or the cargo hold of a bulk carrier is composed of, in wt%: C 0.01-0.30, Si 0.20-1.0,Mn 0.50-1.60, P 0.005-0.040, S 0.005-0.020, Al 0.050-0.100, Cu 0.20-1.0 Ni less than 0.03, Cr 0.05-0.30, Zn 0.001-0.50, Sn 0.005-0.050, Ca 0.0005-0.0050, Fe and unavoidable impurities. A steel material for the upper deck of an oil tanker or the cargo hold of a bulk carrier includes at least one element from each group as followings. The group is composed of Ti 0.050 wt%, Co 0.050 wt% and Mo more than 0.050 wt%, and the group is composed of Bi 0.050 wt% and Sb 0.050 wt%.