HOT-ROLLED STEEL SHEET

摘要

A hot-rolled steel sheet includes a specified chemical composition and includes a steel structure represented by an area ratio of ferrite being 5% to 50%, an area ratio of bainite composed of an aggregate of bainitic ferrite whose grain average misorientation is 0.4° to 3° being 50% to 90%, and a total area ratio of martensite, pearlite, and retained austenite being 5% or less.

主权项

1. A hot-rolled steel sheet comprising:
a chemical composition represented by, in mass %,
C: 0.02% to 0.15%,Si: 0.01% to 2.0%,Mn: 0.05% to 3.0%,P: 0.1% or less,S: 0.03% or less,Al: 0.001% to 0.01%,N: 0.02% or less,O: 0.02% or less,Ti: 0% to 0.2%,Nb: 0% to 0.2%Mo: 0% to 0.2%V: 0% to 0.2%Cr: 0% to 1.0%,B: 0% to 0.01%,Cu: 0% to 1.2%,Ni: 0% to 0.6%,Ca: 0% to 0.005%,REM: 0% to 0.02%, andthe balance: Fe and an impurity; and a steel structure represented by
an area ratio of ferrite: 5% to 50%,an area ratio of bainite composed of an aggregate of bainitic ferrite whose grain average misorientation is 0.4° to 3°:50% to 95%, anda total area ratio of martensite, pearlite, and retained austenite: 5% or less.