Heat resistant ferrite steel with low chromium content and improved durability and toughness

摘要

A low-Cr ferritic steel with improved toughness as well as creep strength is disclosred, which consists essentially of, by weight %: C : 0.03 - 0.12%, Si: 0.70% or less, Mn: 0.10 - 1.50%, Ni: 2.0% or less, Cr: 1.50 - 3.50%, W : 1.0 - 3.0%, V : 0.10 - 0.35%, Nb: 0.01 - 0.10%, B : 0.00010 - 0.020%, N : 0.005% or less, Al: 0.005% or less, Ti: not less than 0.001% but less than 0.05%, Cu: 0.10 - 2.50%, at least one of La, Ce, Y, Ca, Zr, Ta each in an amount of 0 - 0.20%, and Mg in an amount of 0 - 0.05%, Mo in an amount of 0 - 0.40%, and a balance of Fe and incidental impurities including P: not more than 0.030% and S: not more than 0.015%. IMAGE