METHOD FOR MANUFACTURING A HOT PRESS-MOLDED MEMBER

摘要

A method capable of stably mass producing a hot press-formed member having good corrosion resistance after painting from a zinc-based plated steel sheet by hot press forming comprises subjecting a zinc-based plated steel sheet to heat treatment by heating to a temperature region of 600 - 750° C at a rate of temperature increase up to 600° C of at most 50° C per second followed by cooling to 550° C or below, thereby obtaining a steel blank which has a zinc oxide layer in its uppermost surface portion and below it a zinc-iron alloy phase having an Fe content of at least 25 mass %. This steel blank is heated to a temperature of at least its Ac 3 point, then press forming is immediately started at a temperature of at least its Ac 3 point, and then it is rapidly cooled to manufacture a hot press-formed member which has surface region having a zinc oxide phase and an iron-zinc solid solution phase and not containing an intermetallic compound phase or a pure zinc phase.