Method of manufacturing hot press-formed member having excellent productivity, weldability and formability

A method of manufacturing a hot press-formed member, the method comprising:

• heating a blank of an aluminum-based plated steel sheet in a heating furnace;
• removing the heated blank from the heating furnace and conveying the removed blank between an upper mold portion and a lower mold portion of a mold, mounted on a press, to be seated;
• and
• performing a forming process after the upper mold portion of the mold is in contact with the seated blank,
• wherein the heating furnace is a continuous heating furnace comprising section A, section B, and section C provided sequentially in a conveying direction of a blank,
• heating in section A satisfies conditions specified by a figure ‘abcde’ having cumulative in-furnace maintaining times and in-furnace atmospheric temperature coordinates of approximately a(0.2 min, 750° C.), b(1.0 min, 750° C.), c(1.0 min, 800° C.), d(1.5 min, 900° C.), and e(0.2 min, 900° C.),
• heating in section B satisfies conditions specified by a figure ‘fghi’ having cumulative in-furnace maintaining times and atmospheric temperature coordinates of approximately
• f
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• 1.3
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• heating in section C satisfies conditions specified by a figure ‘jklm’ having cumulative in-furnace maintaining times and atmospheric temperature coordinates of approximately
• j
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• 3.7
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• a highest atmospheric temperature of section C is Tb−20° C. or less, based on a highest atmospheric temperature (Tb) of section B,
• t denotes a thickness of a blank and a unit thereof is millimeters (mm),
• when the thickness t is 1.5 mm or less, and an atmospheric temperature of section B is more than 930° C. to less than 940° C.,
• when the thickness t is greater than 1.5 mm, and an atmospheric temperature of section B is more than 940° C. to 960° C. or less, and
• a plating layer of the blank has a thickness of 20 μm or more.