	US 12,084,751 B2
	Method for manufacturing cold-rolled or zinc-plated dual-phase steel plate over 980 MPa
Peng Xue, Shanghai (CN); Li Wang, Shanghai (CN); and Xiaodong Zhu, Shanghai (CN)
Assigned to BAOSHAN IRON & STEEL CO., LTD., Shanghai (CN)
Appl. No. 17/252,031
Filed by BAOSHAN IRON & STEEL CO., LTD., Shanghai (CN)
PCT Filed Jun. 14, 2019, PCT No. PCT/CN2019/091202 § 371(c)(1), (2) Date Dec. 14, 2020, PCT Pub. No. WO2019/242565, PCT Pub. Date Dec. 26, 2019.
Claims priority of application No. 201810631925.4 (CN), filed on Jun. 19, 2018.
Prior Publication US 2021/0254200 A1, Aug. 19, 2021
Int. Cl. C22C 38/14 (2006.01); C21D 8/02 (2006.01); C21D 9/46 (2006.01); C21D 9/68 (2006.01); C21D 11/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C23C 2/00 (2006.01); C23C 2/02 (2006.01); C23C 2/06 (2006.01); C23C 2/20 (2006.01)

CPC C22C 38/14 (2013.01) [C21D 8/0205 (2013.01); C21D 8/0226 (2013.01); C21D 8/0236 (2013.01); C21D 9/46 (2013.01); C21D 9/68 (2013.01); C21D 11/00 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C23C 2/0038 (2022.08); C23C 2/02 (2013.01); C23C 2/022 (2022.08); C23C 2/06 (2013.01); C23C 2/20 (2013.01); C21D 2211/002 (2013.01)]

13 Claims

1. A method for manufacturing a cold-rolled dual-phase steel plate having a strength of at least 980 MPa, wherein a slab is directly transferred to be cold rolled after hot rolling, coiling, bundling, and on-line thermal insulation, and then subjected to continuous annealing to obtain a cold rolled dual-phase steel plate; wherein a coiling temperature is controlled at 450° C. or higher; wherein the online thermal insulation means that each hot-rolled coil is covered with an independent and airtight thermal insulation enclosure within 30 minutes after unloading the coil, and transferred to be cold rolled; wherein a thermal insulation temperature of the hot-rolled coil in the thermal insulation enclosure is 450° C. or higher, and a thermal insulation time is within 20 hours; wherein an electric heating device and a temperature sensor are provided in the thermal insulation enclosure.