High-strength hot-rolled steel sheet and method for manufacturing high-strength hot-rolled steel sheet

A high-strength hot-rolled steel sheet comprising:

• a chemical composition containing, by mass %,
• C:
• 0.04% to 0.18%,
• Si:
• 0.1% to 3.0%,
• Mn:
• 0.5% to 3.5%,
• P:
• more than 0% and 0.100% or less,
• S:
• more than 0% and 0.020% or less, and
• Al:
• more than 0% and 1.5% or less, and
• further containing one or two or more selected from Cr:
• 0.005% to 2.0%, Ti:
• 0.005% to 0.20%, Nb:
• 0.005% to 0.20%, Mo:
• 0.005% to 2.0%, and V:
• 0.005% to 1.0%,
• the balance being Fe and incidental impurities;
• and
• a steel microstructure including, as main phases, 80% to 100% of martensite and bainite in terms of total area fraction,
• wherein an entire area fraction of the martensite dispersed in the bainite is 2% to 20%, and
• among the martensite dispersed in the bainite, an area fraction of the martensite each having an orientation difference of less than 15° between a crystal orientation of the martensite and a crystal orientation of at least one of the bainite adjacent to the martensite is 50% or more relative to the whole martensite dispersed in the bainite.