US 12,435,405 B2
Hot-dipped galvanized steel sheet having excellent bending workability and corrosion resistance and manufacturing method therefor
Sung-Joo Kim, Gwangyang-si (KR); Heung-Yun Kim, Pohang-si (KR); Myung-Soo Kim, Gwangyang-si (KR); Dae-Young Kang, Gwangyang-si (KR); and Yong-Joo Kim, Gwangyang-si (KR)
Assigned to POSCO, Pohang-si (KR)
Appl. No. 17/782,401
Filed by POSCO, Pohang-si (KR)
PCT Filed Dec. 1, 2020, PCT No. PCT/KR2020/017344
§ 371(c)(1), (2) Date Jun. 3, 2022,
PCT Pub. No. WO2021/112519, PCT Pub. Date Jun. 10, 2021.
Claims priority of application No. 10-2019-0162012 (KR), filed on Dec. 6, 2019.
Prior Publication US 2023/0019786 A1, Jan. 19, 2023
Int. Cl. C23C 2/14 (2006.01); B32B 15/01 (2006.01); B32B 15/04 (2006.01); B32B 15/18 (2006.01); C22C 18/00 (2006.01); C22C 18/04 (2006.01); C23C 2/00 (2006.01); C23C 2/06 (2006.01); C23C 2/20 (2006.01); C23C 2/26 (2006.01); C23C 2/28 (2006.01); C23C 2/40 (2006.01); C23C 28/00 (2006.01); C23C 28/02 (2006.01); C23C 30/00 (2006.01)
CPC C23C 2/522 (2022.08) [B32B 15/01 (2013.01); B32B 15/013 (2013.01); B32B 15/04 (2013.01); B32B 15/043 (2013.01); B32B 15/18 (2013.01); C22C 18/00 (2013.01); C22C 18/04 (2013.01); C23C 2/06 (2013.01); C23C 2/14 (2013.01); C23C 2/20 (2013.01); C23C 2/26 (2013.01); C23C 2/261 (2022.08); C23C 2/28 (2013.01); C23C 2/285 (2013.01); C23C 2/40 (2013.01); C23C 28/021 (2013.01); C23C 28/023 (2013.01); C23C 28/025 (2013.01); C23C 28/3225 (2013.01); C23C 30/00 (2013.01); C23C 30/005 (2013.01); Y10T 428/12757 (2015.01); Y10T 428/12799 (2015.01); Y10T 428/12951 (2015.01); Y10T 428/12958 (2015.01); Y10T 428/12972 (2015.01); Y10T 428/2495 (2015.01); Y10T 428/24967 (2015.01); Y10T 428/265 (2015.01); Y10T 428/27 (2015.01)] 6 Claims
OG exemplary drawing
 
1. A hot-dipped galvanized steel sheet comprising:
a base steel sheet;
a Zn—Mg—Al-based plating layer which is provided on at least one surface of the base steel sheet and comprises, by weight:
5.1 to 25% of Al and
4.0 to 10% of Mg,
with a remainder of Zn and other inevitable impurities; and
an interfacial alloy layer having a Fe—Al—Zn composition formed between the base steel sheet and the plating layer,
wherein the interface alloy layer has a thickness of 0.5 to 2 μm and is in a dendritic form, and
wherein the Zn—Mg—Al-based plating layer has:
a structure including one or more of a Zn—Al—MgZn2 ternary eutectic structure, a Zn—MgZn2 binary eutectic structure, a Zn-solid solubilized Al phase structure, and a Zn phase structure; and
a MgZn2 structure including agglomerated Al.