AUSTENITIC STAINLESS STEEL - NIPPON STEEL & SUMITOMO METAL CORP

Title:

AUSTENITIC STAINLESS STEEL

Document Type and Number:

WIPO Patent Application WO/2018/003823

Kind Code:

A1

Abstract:

Provided is an austenitic stainless steel which has excellent carburization resistance even in a high-temperature carburization environment, and which also has excellent hot workability during the production. An austenitic stainless steel according to one embodiment of the present invention has a chemical composition that contains, in mass%, 0.03% or more but less than 0.25% of C, from 0.01% to 2.0% of Si, 2.0% or less of Mn, 10% or more but less than 22% of Cr, more than 30.0% but 40.0% or less of Ni, more than 2.5% but less than 4.5% of Al, from 0.01% to 3.5% of Nb, from 0.0005% to 0.05% of Ca, from 0.0005% to 0.05% of Mg and 0.03% or less of N, with the balance made up of Fe and impurities. The Cr concentration CCr' of the surface layer of this austenitic stainless steel and the Al concentration CAl' of the surface layer of this austenitic stainless steel satisfy formula (1) with respect to the Cr concentration CCr of portions other than the surface layer and the Al concentration CAl of portions other than the surface layer. 0.40 ≤ (CCr'/CAl')/(CCr/CAl) ≤ 0.80 (1)

Inventors:

KOCHI NORIFUMI (JP)
NISHIYAMA YOSHITAKA (JP)

Application Number:

PCT/JP2017/023657

Publication Date:

January 04, 2018

Filing Date:

June 28, 2017

Export Citation:

Click for automatic bibliography generation Help

Assignee:

NIPPON STEEL & SUMITOMO METAL CORP (JP)

International Classes:

C22C38/00; C21D6/00; C21D8/00; C21D8/10; C22C38/58

Foreign References:

JP2015190054A	2015-11-02
JPH02115348A	1990-04-27
JPS61243157A	1986-10-29

Other References: