CAST IRON-BASED AUSTENITE CREEP-RESISTANT STEEL, AND PREPARATION METHOD AND USE THEREFOR

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EP 4 234 744 A8

(12)	CORRECTED EUROPEAN PATENT APPLICATION
	published in accordance with Art. 153(4) EPC

(15)	Correction information:
	Corrected version no 1 (W1 A1)

(48)	Corrigendum issued on:
	18.10.2023 Bulletin 2023/42

(43)	Date of publication:
	30.08.2023 Bulletin 2023/35

(21)	Application number: 22871096.8

(22)	Date of filing: 15.11.2022

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International Patent Classification (IPC):

C22C 38/02^(2006.01)
C22C 38/44^(2006.01)
C22C 33/04^(2006.01)
F04D 29/02^(2006.01)

C22C 38/04^(2006.01)
C22C 38/34^(2006.01)
F01N 13/16^(2010.01)

(52)	Cooperative Patent Classification (CPC):
	F05D 2220/40; F01D 25/005; F05D 2300/171; F05D 2240/14; C22C 38/02; C22C 38/04; C22C 38/001; C22C 38/44

(86)	International application number:
	PCT/CN2022/131885

(87)	International publication number:
	WO 2023/134292 (20.07.2023 Gazette 2023/29)

(84)	Designated Contracting States:
	AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC ME MK MT NL NO PL PT RO RS SE SI SK SM TR
	Designated Extension States:
	BA
	Designated Validation States:
	KH MA MD TN

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Priority:

11.01.2022 CN 202210024961

(71)	Applicant: Kehua Holdings Co., Ltd.
	Yuqiao Development Zone, Zhuze Town, Liyang Changzhou, Jiangsu 213354 (CN)

(72)	Inventors:
	WANG, Yinjie Changzhou, Jiangsu 213354 (CN) GONG, Gaoquan Changzhou, Jiangsu 213354 (CN) CHEN, Xiaohua Changzhou, Jiangsu 213354 (CN)

(74)	Representative: Bayramoglu et al.
	Mira Office Kanuni Sultan Süleyman Boulevard 5387 Street Beytepe, floor 12, no:50 06800 Cankaya, Ankara 06800 Cankaya, Ankara (TR)

(54)	CAST IRON-BASED AUSTENITE CREEP-RESISTANT STEEL, AND PREPARATION METHOD AND USE THEREFOR

(57) The present invention belongs to the technical field of austenitic creep-resistant steel, in particular to a cast iron-based austenitic creep-resistant steel and preparation method and application thereof. The austenitic creep-resistant steel according to the present invention comprises, by mass percentage, the following components: C: 0.2 to 0.5; Si: 0.5 to 2.0; Mn<0.5; Cr: 20 to 28; Ni: 8 to 13; P≤0.04; S≤3; W: 0.5 to 2; N: 0.2 to 0.4; with the balance being iron and other unavoidable impurities. The austenitic creep-resistant steel prepared according to the present invention suppresses the high-temperature ferrite phase and thus eliminating the defects of precipitated nitrogen porosity, reduces the processing cost of castings as compared with the ordinary Cr-Ni-based austenitic heat-resistant steel by optimizing the range of addition of nitrogen and carbon elements, and offers excellent mechanical properties at high temperature and long creep fracture time.