The fire-resistant steel and its production method of being superior in resistance reheat embrittlement characteristic and characteristic of the welded joint section

摘要

As for this invention, being something which offers strength at elevated temperature and the fire-resistant steel which is superior in resistance reheat embrittlement characteristic and characteristic of the welded joint section, being the steel of room temperature strength 400 - 600N/mm2 class, as a principal component, C: Under 0.05% of 0.010% or more, Si: 0.01 - 0.50%, Mn: 0.80 - 2.00%, Cr: Under 2.00% of 0.50% or more, V: 0.03 - 0.30%, Nb: 0.01 - 0.10%, N: 0.001 - 0.010%, Al: It contains 0.005 - 0.10%, restricts each content of Ni, Cu, Mo and B, it is produced each element, 4Cr [%] 5Mo [%] 10Ni [%] 2Cu [%] Mn [%] making use of the steel which satisfies the relationship which is displayed with 0.