Method of manufacturing a hot-stamped part

A method of manufacturing a part to be hot-stamped, the method comprising:

• inserting a plurality of blanks into a heating furnace, wherein the heating furnace includes heating sections and soaking sections;
• step heating the plurality of blanks as the plurality of blanks passes through the heating sections;
• soaking the plurality of blank at a temperature of Ac3 to 1,000° C. as the plurality of blanks passes through the soaking sections;
• transferring the soaked plurality of blanks from the heating furnace to a press mold;
• forming a molded body by hot-stamping the transferred plurality of blanks;
• and
• cooling the formed molded body,
• wherein, in the step of heating the plurality of blanks, a temperature condition in the heating furnace satisfies formula:
• 0<(Tg−Ti)/Lt<0.025° C./mm
• wherein Tg denotes a soaking temperature (C), Ti denotes an initial temperature (C) of the heating furnace, and Lt denotes a total length (mm) of the heating sections,
• wherein the soaking is performed in the soaking sections having same temperature range in the heating furnace,
• wherein the plurality of blanks includes a first blank and a second blank having different thicknesses, and
• wherein the first blank and the second blank are simultaneously inserted into the heating furnace.