	US 12,297,514 B2
	High strength hot rolled steel having excellent scale adhesivness and a method of manufacturing the same
Eva Diaz Gonzalez, Deinze (BE); Lieven Bracke, Sinaai (BE); Tom Waterschoot, Lokeren (BE); and Joost Destrycker, Zele (BE)
Assigned to ArcelorMittal, Luxembourg (LU)
Appl. No. 17/278,085
Filed by ArcelorMittal, Luxembourg (LU)
PCT Filed Sep. 25, 2019, PCT No. PCT/IB2019/058125 § 371(c)(1), (2) Date Mar. 19, 2021, PCT Pub. No. WO2020/065549, PCT Pub. Date Apr. 2, 2020.
Claims priority of application No. PCT/IB2018/057384 (WO), filed on Sep. 25, 2018.
Prior Publication US 2021/0348245 A1, Nov. 11, 2021
Int. Cl. C21D 8/00 (2006.01); C21D 6/00 (2006.01); C21D 6/04 (2006.01); C21D 8/02 (2006.01); C21D 9/46 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/06 (2006.01); C22C 38/10 (2006.01); C22C 38/42 (2006.01); C22C 38/44 (2006.01); C22C 38/46 (2006.01); C22C 38/48 (2006.01); C22C 38/50 (2006.01); C22C 38/54 (2006.01); C22C 38/58 (2006.01)

CPC C21D 8/0226 (2013.01) [C21D 6/004 (2013.01); C21D 6/005 (2013.01); C21D 6/008 (2013.01); C21D 9/46 (2013.01); C22C 38/001 (2013.01); C22C 38/02 (2013.01); C22C 38/06 (2013.01); C22C 38/42 (2013.01); C22C 38/44 (2013.01); C22C 38/46 (2013.01); C22C 38/48 (2013.01); C22C 38/50 (2013.01); C22C 38/54 (2013.01); C22C 38/58 (2013.01); C21D 2211/005 (2013.01)]

16 Claims

1. A hot rolled steel product having a composition comprising in percentage by weight:

0.06%≤Carbon≤0.18%

0.01%≤Nickel≤0.6%

0.001%≤Copper≤2%

0.001%≤Chromium≤2%

0.001%≤Silicon≤0.8%

0%≤Nitrogen≤0.008%

0%≤Phosphorus≤0.03%

0%≤Sulfur≤0.03%

0.001%≤Molybdenum≤0.5%

0.001%≤Niobium≤0.1%

0.001%≤Vanadium≤0.5%

0.001%≤Titanium≤0.1%;

and optionally one or more of the following elements:

0.2%≤Manganese≤2%

0.005%≤Aluminum≤0.1%

0% ≤Boron≤0.003%

0% ≤Calcium≤0.01%

0% ≤Magnesium≤0.010%;

a remainder of the composition being composed of iron and unavoidable impurities caused by processing,

the product having a tertiary scale layer including, in area fraction, a total amount of at least 50% of magnetite and ferrite, wherein ferrite is at least 25%, 0% to 50% of wustite, and 0% to 10% of hematite, the tertiary scale layer having a thickness between 5 microns and 40 microns.