US 12,447,563 B2
Wire rod for welding rods and method for manufacturing same
Bong-Keun Lee, Pohang-si (KR); and Sung-Hoon Chung, Pohang-si (KR)
Assigned to POSCO, Pohang-si (KR)
Appl. No. 17/765,777
Filed by POSCO, Pohang-si (KR)
PCT Filed Oct. 6, 2020, PCT No. PCT/KR2020/013581
§ 371(c)(1), (2) Date Mar. 31, 2022,
PCT Pub. No. WO2021/075777, PCT Pub. Date Apr. 22, 2021.
Claims priority of application No. 10-2019-0128586 (KR), filed on Oct. 16, 2019.
Prior Publication US 2022/0371131 A1, Nov. 24, 2022
Int. Cl. B23K 35/02 (2006.01); B23K 35/30 (2006.01); B23K 35/40 (2006.01); C21D 9/52 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01)
CPC B23K 35/0261 (2013.01) [B23K 35/3066 (2013.01); B23K 35/3073 (2013.01); B23K 35/40 (2013.01); C21D 9/525 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C21D 2211/001 (2013.01)] 6 Claims
OG exemplary drawing
 
1. A wire rod for welding rods comprising, by weight:
0.05 to 0.37% of carbon (C),
18 to 31% of manganese (Mn),
0.05 to 0.7% of silicon (Si),
0.1% or less or nitrogen (N),
0.02% or less of phosphorus (P),
0.01% or less of sulfur(S),
one or more selected from the group consisting of:
8% or less of nickel (Ni),
2.95% or less of chromium (Cr),
2.5% or less of molybdenum (Mo), and
0.3% or less of vanadium (V), and
a balance of Fe and unavoidable impurities,
wherein the following Relation 1 is satisfied:
Mn+1.6Ni+15(C+N)≥24,  [Relation 1]
wherein the following Relation 2 is satisfied:
10(C+N)+1.5Cr+2Mo+1.5V−0.1Mn−0.16Ni≥0, and  [Relation 2]
wherein each element in the Relations 1 and 2 refers to a content by weight of the element, and
wherein when welding is performed using the wire rod, a weld zone having a Charpy impact toughness at −196° C. of 27 J or more is formed.