HOT-ROLLED STEEL SHEET OR PLATE

摘要

This hot-rolled steel sheet or plate contains given chemical components and has a structure comprising, in terms of areal proportion, 5-60% ferrite and 30-95% bainite. In the structure, in the case where each boundary where the difference in orientation is 15º or greater is taken as a grain boundary and regions each surrounded by grain boundaries and each having an equivalent circular diameter of 0.3 µm or larger are defined as crystal grains, the proportion of crystal grains which each have an in-grain orientation difference of 5-14º is 20-100% in terms of areal proportion.