US 11,655,518 B2
Steel material for taylor welded blank and method for manufacturing hot-stamped part using same steel
Byung Gil Yoo, Seoul (KR); Hyeong Hyeop Do, Chungcheongnam-do (KR); Chee Woong Song, Seoul (KR); Do Hak Kim, Gyeongsangbuk-do (KR); Young Mun Shin, Chungcheongnam-do (KR); Soon Geun Jang, Sejong (KR); and Sang Mun Hong, Gyeongsangbuk-do (KR)
Assigned to Hyundai Steel Company, Incheon (KR)
Filed by Hyundai Steel Company, Incheon (KR)
Filed on Nov. 16, 2021, as Appl. No. 17/527,249.
Application 17/527,249 is a division of application No. 16/625,431, previously published as PCT/KR2017/015716, filed on Dec. 29, 2017.
Claims priority of application No. 10-2017-0081280 (KR), filed on Jun. 27, 2017; and application No. 10-2017-0168403 (KR), filed on Dec. 8, 2017.
Prior Publication US 2022/0074017 A1, Mar. 10, 2022
Int. Cl. C21D 9/50 (2006.01); B21D 22/02 (2006.01); C21D 6/00 (2006.01); C21D 8/02 (2006.01); C22C 38/04 (2006.01); C22C 38/12 (2006.01); C22C 38/14 (2006.01)
CPC C21D 9/50 (2013.01) [B21D 22/022 (2013.01); C21D 6/005 (2013.01); C21D 8/0205 (2013.01); C21D 8/0226 (2013.01); C21D 8/0236 (2013.01); C21D 8/0263 (2013.01); C22C 38/04 (2013.01); C22C 38/12 (2013.01); C22C 38/14 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01)] 7 Claims
OG exemplary drawing
1. A method for manufacturing a hot-stamped part, comprising the steps of:
(a) preparing a first blank using a steel slab comprising 0.04 to 0.06 wt % of carbon (C), 1.2 to 1.5 wt % of manganese (Mn), 0.01 to 0.10 wt % of titanium (Ti), 0.01 to 0.10 wt % of niobium (Nb), and the balance of iron (Fe) and inevitable impurities, and a second blank obtained by cutting a steel plate provided separately from the first blank;
wherein the first blank is prepared by the steps comprising:
(a-1) finish-hot-rolling the steel slab at a finishing delivery temperature (FDT) of 860° C. to 920° C.,
(a-2) cooling the hot-rolled steel slab to a coiling temperature (CT) of 640° C. to 660° C., followed by coiling,
(a-3) uncoiling the coiled steel slab, followed by cold rolling, and
(a-4) subjecting the cold-rolled steel slab to annealing heat treatment; and
(b) welding the first and second blanks to each other by a tailor-welded blank process, thereby forming a joined steel material;
(c) hot-stamping the joined steel material in a press mold, thereby forming a molded body; and
(d) cooling the molded body, thereby forming a hot-stamped part.