US 11,884,997 B2
Hot rolled plate or forging of an austenitic steel
Bernard Bonnefois, Le Breuil (FR); Amelie Fanica, Cersot (FR); Lionel Coudreuse, Saint-Etienne (FR); Tassa Oriana, Rome (IT); and Johannes Cornelis Van Wortel, Ga Brummen (NL)
Assigned to ArcelorMittal, Luxembourg (LU)
Filed by ArcelorMittal, Luxembourg (LU)
Filed on Mar. 21, 2022, as Appl. No. 17/699,324.
Application 17/699,324 is a continuation of application No. 15/991,428, filed on May 29, 2018, abandoned.
Application 15/991,428 is a continuation of application No. 13/386,141, abandoned, previously published as PCT/IB2010/001759, filed on Jul. 20, 2010.
Claims priority of application No. 09290581 (EP), filed on Jul. 22, 2009.
Prior Publication US 2023/0040035 A1, Feb. 9, 2023
Int. Cl. C22C 38/00 (2006.01); C22C 38/46 (2006.01); C22C 38/54 (2006.01)
CPC C22C 38/001 (2013.01) [C22C 38/46 (2013.01); C22C 38/54 (2013.01); C21D 2211/001 (2013.01)] 22 Claims
 
1. A hot rolled plate or forging of an austenitic steel non-susceptible to relaxation cracking, with composition comprising, in percentages by weight:
0.019%≤C≤0.030%
0.5%≤Mn≤3%
0.1%≤Si≤0.75%
Al≤0.25%
18%≤Cr≤25%
12%≤Ni≤20%
1.5%≤Mo≤3%
0.001%≤B≤0.008%
0.25%≤V≤0.35%
0.23%≤N≤0.27%,
the balance being iron and unavoidable impurities, and wherein:
Ni(eq.)≥1.11 Cr(eq.)−8.24, wherein:
Cr(eq)=Cr+Mo+1.5Si+5V+3Al+0.02
Ni(eq)=Ni+30C+x(N−0.045)+0.87 wherein:
x=22 for 0.23%≤N≤0.25%
x=20 for 0.25%<N≤0.27%; and
a fully austenitic structure.