| 摘要 |
PROBLEM TO BE SOLVED: To provide a hot rolled steel sheet for a hot press suitable as a forming member of a hot press formed member having a strength of≥1,000 MPa and used for automobiles and various industrial equipment. SOLUTION: The hot rolled steel sheet for a hot press has a steel composition comprising 0.10 to 0.50% C, 0.02 to 2.0% Si, 0.3 to 3.5% Mn, 0.03 to 1.0% Cr, 0.0003 to 0.0050% B,≤0.10% P,≤0.05% S,≤2.0% Al and≤0.01% N, and the balance Fe with impurities, and has a structure containing ferrite of≥30% by area, and the balance one or two selected from pearlite and cementite, wherein the average crystal grain size of ferrite is 2 to 25μm, and a sheet thickness is 1.6 to 6.0 mm. COPYRIGHT: (C)2007,JPO&INPIT
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