Austenitic alloy

Patent metadata

Field	Value
Publication number	US-9587295-B2
Application number	US-201314372760-A
Country	US
Kind code	B2
Filing date	Jan 16, 2013
Priority date	Jan 18, 2012
Publication date	Mar 7, 2017
Grant date	Mar 7, 2017

Abstract

An austenitic alloy comprising (in weight %):
C: 0.01-0.05 Si: 0.05-0.80 Mn: 1.5-2 Cr: 26-34.5 Ni: 30-35 Mo: 3-4 Cu: 0.5-1.5 N: 0.05-0.15 V: <0.15

the balance being Fe and unavoidable impurities, wherein 40<% Ni+100*% N<50.

First claim

The invention claimed is:

1. Austenitic alloy comprising in weight %:
C: 0.01-0.015
Si: 0.40-0.52
Mn: 1.7
Cr: 27
Ni: 33
Mo: 3.4
Cu: 0.9-1.0
N: 0.09-0.11
V: 0.07-0.09
the balance being Fe and unavoidable impurities,
wherein the weight % of N and Ni is balanced to fulfill the requirement 40<% Ni+100*% N<45,
wherein a creep test at 600° C. and a stress of 160 MPa exhibits a rupture elongation of 71 to 90% and a time to rupture of at least 100,000 hours,
wherein a creep test at 650° C. and a stress of 95 to 105 MPa exhibits a rupture elongation of 31 to 70% and a time to rupture of at least 95,000 hours, and
wherein the alloy has a microstructure that includes a MX phase.

2. The austenitic alloy according to claim 1 , wherein the time to rupture for the creep test at 600° C. and stress of 160 MPa is from 100,000 hours to about 117,500 hours, and wherein the time to rupture for the creep test at 650° C. and stress of 95 to 105 MPa is from 95,000 hours to about 188,000 hours.

3. A component for a combustion plant, the component comprising an austenitic alloy in weight %:
C: 0.01-0.015
Si: 0.40-0.52
Mn: 1.7
Cr: 27
Ni: 33
Mo: 3.4
Cu: 0.9-1.0
N: 0.09-0.11
V: 0.07-0.09
the balance being Fe and unavoidable impurities,
wherein 40<% Ni+100*% N<45, and
wherein a creep test at 600° C. and a stress of 160 MPa exhibits a rupture elongation of 71 to 90% and a time to rupture from about 100,000 hours to about 117,500 hours
wherein a creep test at 650° C. and a stress of 95 to 105 MPa exhibits a rupture elongation of 31 to 70% and a time to rupture of from about 95,000 hours to about 188,000 hours, and
wherein the alloy has a microstructure that includes a MX phase.

4. A component for a combustion plant according to claim 3 , wherein said component is a superheater.

5. A component for a combustion plant according to claim 3 , wherein said component is a reheater.

6. A component for a combustion plant according to claim 3 , wherein said component is an evaporator.

7. Austenitic alloy comprising in weight %:
C: 0.009-0.014
Si: 0.40-0.52
Mn: 1.70-1.73
Cr: 27.11-27.29
Ni: 33.21-33.45
Mo: 3.42-3.44
Cu: 0.95-0.98
N: 0.093-0.11
V: 0.07-0.09
the balance being Fe and unavoidable impurities,
wherein the weight % of N and Ni is balanced to fulfill the requirement 40<%Ni+100*% N<45,
wherein a creep test at 600° C. and a stress of 160 MPa exhibits a rupture elongation of 71 to 90% and a time to rupture from about 100,000 hours to about 117,500 hours,
wherein a creep test at 650° C. and a stress of 95 to 105 MPa exhibits a rupture elongation of 31 to 70% and a time to rupture of from about 95,000 hours to about 188,000 hours, and
wherein the alloy has a microstructure that includes a MX phase.

8. The austenitic alloy according to claim 7 , wherein the time to rupture for the creep test at 600° C. and stress of 160 MPa is from 102,321 hours to 117,561 hours, and wherein the time to rupture for the creep test at 650° C. and stress of 95 to 105 MPa is from 95,883 hours to 188,609 hours.

Assignees

• Sandvik Intellectual Property

Inventors

• Chai Guocai
• Hogberg Jan
• Akesson Sofia
• Forsberg Urban

Classifications

• C22C38/001

  containing N · CPC title

• C22C38/58

  with more than 1.5% by weight of manganese · CPC title

• C22C38/46

  with vanadium · CPC title

• C21D2211/001

  Austenite · CPC title

• C22C38/42

  with copper · CPC title