A method for manufacturing a hot press member, a steel plate for hot press, and a method for manufacturing a hot press member.

摘要

Provided is a hot press member having excellent indentation peel strength. The tensile strength of the hot press member is 1780 MPa or more. The ten-point average roughness Rzjis of the surface of the plating layer is 25 μm or less. The steel plate has C: 0.25% or more and less than 0.50%, Si: 1.5% or less, Mn: 1.1% or more and 2.4% or less, P: 0.05% or less, S in mass%. : 0.005% or less, Al: 0.01% or more and 0.50% or less, N: 0.010% or less, Sb: 0.001% or more and 0.020% or less, Nb: 0.005% or more 0. It contains 15% or less and Ti: 0.005% or more and 0.15% or less, and the balance consists of Fe and unavoidable impurities. Within 50 μm in the plate thickness direction from the surface of the steel sheet excluding the plating layer, the average crystal grain size of the old austenite is 7 μm or less, and the volume fraction of martensite is 90% or more.