STEEL PRODUCT FOR USE AS LINE PIPE HAVING HIGH HIC RESISTANCE AND LINE PIPE PRODUCED USING SUCH STEEL PRODUCT

摘要

A steel product for a line pipe according to the invention has acomposition containing, in mass %, C : 0.03% to 0.15%, Si : 0.05% to 1.0%,Mn : 0.5% to 1.8%, P : 0.015% or less, S: 0.004% or less, O : 0.01% or less,N: 0.007% or less, sol. Al :0.01% to 0.1%, Ti :0.024% or less, Ca :0.0003% to 0.02%, and the balance consisting of Fe and impurities. Thesize of TiN in the steel product for a line pipe is at most 30 µm. Thesteelproduct has high HIC resistance and its crack area ratio can be reduced to3% or less.