Patent ID: 11473159

Abstract:
Provided is a hot rolled steel sheet comprising a predetermined composition wherein the hot rolled steel sheet comprises first ferrite with an average orientation difference in the same grain of 0.5 to 5.0° in 30 to 70 vol %, at least one type of structures among bainite and second ferrite with an average orientation difference of 0 to less than 0.5° and the first ferrite in a total of 95 vol % or more, a balance microstructure of 5 vol % or less, has an average grain size of the first ferrite of 0.5 to 5.0 μm, and has an average grain size of the other structures of 1.0 to 10 μm. Provided is a method for producing a hot rolled steel sheet comprising rolling where two or more consecutive passes of rolling including a final pass are performed under conditions of a rolling temperature: A point or more and less than Ae3 point etc., and where a total strain amount of all passes satisfying the conditions is 1.4 to 4.0, cooling by a 20 to 50° C./sec average cooling rate, and coiling the steel sheet at 300° C. to 600° C.