IP Library Granted Patent US 12,221,707
Granted Patent B2
US 12,221,707 · App. 17/297,938 · Granted Feb 11, 2025

Acid-resistant steel sheet and manufacturing method therefor

Inventors: Minho Jo (Pohang-si, KR); Byoung Ho Lee (Pohang-si, KR); Young-Kwang Hong (Pohang-si, KR)
Assignee: POSCO CO., LTD
C23F11/04C21D6/005C21D6/008C21D8/0205C21D8/0226C21D8/0236C21D8/0263C21D9/46C22C38/001C22C38/002C22C38/02C22C38/04C22C38/06
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Quick Facts
Patent No.
US 12,221,707
App. No.
17/297,938
Granted
Feb 11, 2025
Kind
B2
Abstract

An acid-resistant steel sheet according to an embodiment of the present invention includes, by wt %, equal to or less than 0.1% of C (excluding 0%) and 2.0 to 4.0% of Si, and includes a remainder of Fe and inevitable impurities, and the content of Si of the surface portion by the inward depth of up to 10 μm from the surface of the steel sheet is equal to or greater than 15 wt %.

Claims (11)

1. An acid-resistant hot-rolled steel sheet comprising,

by wt %, equal to or less than 0.1% of C excluding 0% and 2.0 to 4.0% of Si, and a remainder of Fe and inevitable impurities,

wherein the content of Si of the surface portion by the inward depth of up to 10 μm from the surface of the steel sheet is equal to or greater than 15 wt %.

2. The acid-resistant hot-rolled steel sheet of claim 1 , further comprising

at least one of 0.1 to 0.5 wt % of Mn, equal to or less than 0.1 wt % of Al, equal to or less than 0.01 wt % of P, equal to or less than 0.01 wt % of S, and equal to or less than 0.01 wt % of N.

3. The acid-resistant hot-rolled steel sheet of claim 1 , further comprising

equal to or less than 0.1 wt % of Cr, equal to or less than 0.1 wt % of Ni, equal to or less than 0.1 wt % of Cu, equal to or less than 0.1 wt % of Nb, and equal to or less than 0.1 wt % of Mo.

4. The acid-resistant hot-rolled steel sheet of claim 1 , wherein

when soaked for an hour in a 1 wt % sulfuric acid solution at 70° C., an average corrosion rate is equal to or less than 3.5 mg/cm 2 ·h.

5. The acid-resistant hot-rolled steel sheet of claim 1 , wherein

an elongation rate is equal to or greater than 30%.

Assignments (3)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 26, 2022
From: POSCO HOLDINGS INC.
To: POSCO CO., LTD
Reel/Frame 061777/0937 →
CHANGE OF NAME Recorded Sep 28, 2022
From: POSCO
To: POSCO HOLDINGS INC.
Reel/Frame 061561/0730 →
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded May 27, 2021
From: JO, MIN HO; LEE, BYOUNG HO; HONG, YOUNG-KWANG
To: POSCO
Reel/Frame 056378/0624 →
Priority Claims (1)
KR 10-2018-0153136 · Nov 30, 2018 · national
Continuity (1)
Related Publication 20220042179A1 · Feb 10, 2022
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