US 11,891,674 B2
High-strength multiphase tinned steel raw plate and manufacturing method therefor
Fuliang Lian, Shanghai (CN); Gaofei Liang, Shanghai (CN); Hongxing Chen, Shanghai (CN); Shunli Zhao, Shanghai (CN); Bijun Ban, Shanghai (CN); Xiujun Li, Shanghai (CN); and Gang Xu, Shanghai (CN)
Assigned to BAOSHAN IRON & STEEL CO., LTD., Shanghai (CN)
Appl. No. 16/642,433
Filed by BAOSHAN IRON & STEEL CO., LTD., Shanghai (CN)
PCT Filed Aug. 28, 2018, PCT No. PCT/CN2018/102619
§ 371(c)(1), (2) Date Feb. 27, 2020,
PCT Pub. No. WO2019/042268, PCT Pub. Date Mar. 7, 2019.
Claims priority of application No. 201710761690.6 (CN), filed on Aug. 30, 2017.
Prior Publication US 2020/0255915 A1, Aug. 13, 2020
Int. Cl. C22C 38/04 (2006.01); C21D 8/02 (2006.01); C21D 1/26 (2006.01); C21D 6/00 (2006.01); C22C 38/00 (2006.01); C22C 38/06 (2006.01); C22C 38/20 (2006.01); C22C 38/22 (2006.01); C22C 38/26 (2006.01); C22C 38/28 (2006.01); C22C 38/32 (2006.01)
CPC C21D 8/0247 (2013.01) [C21D 1/26 (2013.01); C21D 6/002 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 8/0205 (2013.01); C21D 8/0236 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/20 (2013.01); C22C 38/22 (2013.01); C22C 38/26 (2013.01); C22C 38/28 (2013.01); C22C 38/32 (2013.01); C21D 2211/003 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01); C21D 2211/009 (2013.01)] 12 Claims
 
1. A multiphase steel tinned raw plate, having a chemical composition consisting of, by mass percentage, C: 0.081-0.14%, Mn: 0.2-0.8%, Al: 0.01-0.09%, P: 0.01-0.03%, N: 0.002-0.015%, Cu: 0.005-0.03%, one or more elements selected from the group consisting of B: 0.001-0.005%, Cr: 0.005-0.05%, Ti: 0.001-0.1%, Nb: 0.001-0.2%, and Mo: 0.001-0.008%, and a balance of Fe and unavoidable impurities, wherein the following relationship is met: 0.21%≤Mn+1.3Cr+3.2Mo+0.5Cu≤0.91%, wherein the multiphase steel tinned raw plate has a structure consisting of ferrite grains, pearlite, martensite and cementite particles,
wherein the pearlite, martensite, and cementite particles in the structure of the multiphase steel tinned raw plate have a volume fraction of 5-20%, and the martensite in the structure of the multiphase steel tinned raw plate has a volume fraction of equal to or higher than 1% to less than 5%; and
wherein, after baking at 150-300° C. for 15-60 min, the multiphase steel tinned raw plate has a yield strength Rp0.2≥(400+12×DCR)MPa, and an elongation A≥(25−1.2×DCR) %, wherein DCR represents a reduction rate of double cold reduction, wherein 5%≤DCR≤18%.