	US 12,221,681 B2
	Steel plate for high temperature applications having excellent strength at high temperature and method for manufacturing the same
Soon-Taik Hong, Pohang-si (KR)
Assigned to POSCO CO., LTD, Pohang-si (KR)
Appl. No. 17/297,111
Filed by POSCO, Pohang-si (KR)
PCT Filed Nov. 29, 2019, PCT No. PCT/KR2019/016700 § 371(c)(1), (2) Date May 26, 2021, PCT Pub. No. WO2020/111859, PCT Pub. Date Jun. 4, 2020.
Claims priority of application No. 10-2018-0150818 (KR), filed on Nov. 29, 2018.
Prior Publication US 2022/0025495 A1, Jan. 27, 2022
Int. Cl. C22C 38/44 (2006.01); C21D 8/02 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/42 (2006.01)

CPC C22C 38/44 (2013.01) [C21D 8/0205 (2013.01); C21D 8/0226 (2013.01); C21D 9/46 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01)]

6 Claims

1. A steel plate for high temperature applications having excellent post weld heat treatment (PWHT) resistance, comprising, by wt %:

0.05 to 0.25% of C,

0.1 to 1.0% of Mn,

0.1 to 0.8% of Si,

1 to 3% of Cr,

0.05 to 0.3% of Cu,

0.5 to 1.5% of Mo,

0.05 to 0.5% of Ni,

0.005 to 0.1% of Al,

one or more of 0.005 to 0.10% of Ir and 0.005 to 0.10% of Rh,

a balance of Fe, and

inevitable impurities,

wherein the steel plate has a microstructure comprised of 50 area % or more of tempered martensite, and a remainder of residual tempered bainite.