AUSTENITIC STAINLESS STEEL SHEET FOR EXHAUST COMPONENT HAVING EXCELLENT HEAT RESISTANCE AND WORKABILITY, TURBOCHARGER COMPONENT, AND METHOD FOR PRODUCING AUSTENITIC STAINLESS STEEL SHEET FOR EXHAUST COMPONENT

• US 20200131595A1
• Filed: 03/23/2017
• Published: 04/30/2020
• Est. Priority Date: 03/23/2016
• Status: Active Grant

• Current Assignee: Nippon Steel & Sumikin Stainless Steel Corporation (Nippon Steel Corporation)
• Original Assignee: Nippon Steel & Sumikin Stainless Steel Corporation (Nippon Steel Corporation)
• Inventors: HAMADA, Junichi, TAKUSHIMA, Chikako, YAKAWA, Atsuhisa
• Granted Patent: US 10,894,995 B2
• Time in Patent Office: Days
• CPC Class Codes: C21D 2211/001 Austenite
• CPC Class Codes: C21D 6/004 containing Cr and Ni
• CPC Class Codes: C21D 6/005 containing Mn
• CPC Class Codes: C21D 6/008 containing Si
• CPC Class Codes: C21D 8/0205 of ferrous alloys
• CPC Class Codes: C21D 8/0236 Cold rolling
• CPC Class Codes: C21D 8/0247 characterised by the heat treatment
• CPC Class Codes: C21D 9/46 for sheet metals
• CPC Class Codes: C22C 38/00 Ferrous alloys, e.g. steel alloys cast-iron alloys C22C37/00
• CPC Class Codes: C22C 38/001 containing N
• CPC Class Codes: C22C 38/002 containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
• CPC Class Codes: C22C 38/005 containing rare earths, i.e. Sc, Y, Lanthanides
• CPC Class Codes: C22C 38/008 containing tin
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/04 containing manganese
• CPC Class Codes: C22C 38/06 containing aluminium
• CPC Class Codes: C22C 38/34 with more than 1.5% by weight of silicon
• CPC Class Codes: C22C 38/42 with copper
• CPC Class Codes: C22C 38/44 with molybdenum or tungsten
• CPC Class Codes: C22C 38/46 with vanadium
• CPC Class Codes: C22C 38/48 : with niobium or tantalum
• CPC Class Codes: C22C 38/50 : with titanium or zirconium
• CPC Class Codes: C22C 38/54 : with boron
• CPC Class Codes: C22C 38/58 : with more than 1.5% by weight of manganese
• CPC Class Codes: C22C 38/60 : containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
• CPC Class Codes: F01N 3/2803 : characterised by structure, by material or by manufacturing of catalyst support
• CPC Class Codes: F02B 39/00 : Component parts, details, or accessories relating to, driven charging or scavenging pumps, not provided for in groups F02B33/00 - F02B37/00
• CPC Class Codes: F04C 29/04 : Heating; Cooling of machines or engines in general F01P; Heat insulation heat insulation in general F16L59/00

Abstract

The present invention particularly has as its technical problem to provide austenitic stainless steel sheet used as the material for housings of turbochargers in which excellent heat resistance and workability are demanded. The austenitic stainless steel sheet according to the present invention comprises, by mass %, C: 0.005 to 0.2%, Si: 0.1 to 4%, Mn: 0.1 to 10%, Ni: 2 to 25%, Cr: 15 to 30%, N: 0.01 to less than 0.4%, Al: 0.001 to 1%, Cu: 0.05 to 4%, Mo: 0.02 to 3%, V: 0.02 to 1%, P: 0.05% or less, and S: 0.01% or less, comprises a balance of Fe and unavoidable impurities, and has an annealing twin frequency of 40% or more and is excellent in heat resistance.

Claims

1. Austenitic stainless steel sheet for an exhaust component having excellent heat resistance comprising, by mass %, C:

0.005 to 0.2%, Si;

0.1 to 4%, Mn;

0.1 to 10%, Ni;

2 to 25%, Cr;

15 to 30%, N;

0.01 to less than 0.4%, Al;

0.001 to 1%, Cu;

0.05 to 4%, Mo;

0.02 to 3%, V;

0.02 to 1%, P;

0.05% or less, and S;

0.01% or less, comprising a balance of Fe and unavoidable impurities, and having an annealing twin frequency of 40% or more.

2. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1 wherein said steel sheet further comprises, by mass %, N:

over 0.04% to less than 0.4% and/or Si;

over 1.0% to less than 3.5%.

3. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1 wherein said steel sheet further comprises, by mass %, N:

over 0.15% to less than 0.4%.

4. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1 wherein said steel sheet further comprises, by mass %, one or more of Ti:

0.005 to 0.3%, Nb;

0.005 to 0.3%, B;

0.0002 to 0.005%, Ca;

0.0005 to 0.01%, W;

0.1 to 3.0%, Zr;

0.05 to 0.30%, Sn;

0.01 to 0.50%, Co;

0.03 to 0.30%, Mg;

0.0002 to 0.010%, Sb;

0.005 to 0.3%, REM;

0.002 to 0.2%, Ga;

0.0002 to 0.3%, and Ta;

0.01 to 1.0%.

5. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1 wherein said steel sheet further comprises, by mass %, Ti:

over 0.03% to 0.3% and/or Nb;

0.005 to 0.05%.

6. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1 wherein said steel sheet has a high temperature yield strength at 900°

C. of 70 Mp or more.

7. A method for producing austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 1, said method for producing stainless steel sheet comprising steps of cold rolling and annealing the cold rolled sheet, wherein in the step of cold rolling, a reduction is in a range of 60% or less and wherein in the step of annealing the cold rolled sheet, a heating rate at a temperature which is less than 900°

C. is less than 10°

C./sec, a heating rate at a temperature of 900°

C. and more is 10°

C./sec or more, and a highest temperature is in a range of from 1000 to 1200°

C.

8. The austenitic stainless steel sheet according to claim 1 used for at least one of a housing forming an outer shell of a turbocharger and a precision component at the inside of a nozzle vane type turbocharger.

9. The austenitic stainless steel sheet according to claim 1 used for at least one of a back plate, oil deflector, compressor wheel, nozzle mount, nozzle plate, nozzle vane, drive ring, and drive lever inside of a nozzle vane type turbocharger.

10. An exhaust component fabricated using austenitic stainless steel sheet according to claim 1.

11. An exhaust component wherein at least one of a housing forming an outer shell of a turbocharger and a precision part inside of a nozzle vane type turbocharger is fabricated using austenitic stainless steel sheet according to claim 1.

12. A housing forming an outer shell of a turbocharger fabricated using austenitic stainless steel sheet according to claim 1.

13. A nozzle vane type turbocharger wherein at least one of a back plate, oil deflector, compressor wheel, nozzle mount, nozzle plate, nozzle vane, drive ring, and drive lever is fabricated using austenitic stainless steel sheet according to claim 1.

14. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 2 wherein said steel sheet further comprises, by mass %, N:

over 0.15% to less than 0.4%.

15. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 2 wherein said steel sheet further comprises, by mass %, one or more of Ti:

0.005 to 0.3%, Nb;

0.005 to 0.3%, B;

0.0002 to 0.005%, Ca;

0.0005 to 0.01%, W;

0.1 to 3.0%, Zr;

0.05 to 0.30%, Sn;

0.01 to 0.50%, Co;

0.03 to 0.30%, Mg;

0.0002 to 0.010%, Sb;

0.005 to 0.3%, REM;

0.002 to 0.2%, Ga;

0.0002 to 0.3%, and Ta;

0.01 to 1.0%.

16. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 3 wherein said steel sheet further comprises, by mass %, one or more of Ti:

0.005 to 0.3%, Nb;

0.005 to 0.3%, B;

0.0002 to 0.005%, Ca;

0.0005 to 0.01%, W;

0.1 to 3.0%, Zr;

0.05 to 0.30%, Sn;

0.01 to 0.50%, Co;

0.03 to 0.30%, Mg;

0.0002 to 0.010%, Sb;

0.005 to 0.3%, REM;

0.002 to 0.2%, Ga;

0.0002 to 0.3%, and Ta;

0.01 to 1.0%.

17. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 2 wherein said steel sheet further comprises, by mass %, Ti:

over 0.03% to 0.3% and/or Nb;

0.005 to 0.05%.

18. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 3 wherein said steel sheet further comprises, by mass %, Ti:

over 0.03% to 0.3% and/or Nb;

0.005 to 0.05%.

19. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 4 wherein said steel sheet further comprises, by mass %, Ti:

over 0.03% to 0.3% and/or Nb;

0.005 to 0.05%.

20. The austenitic stainless steel sheet for an exhaust component having excellent heat resistance and workability according to claim 2 wherein said steel sheet has a high temperature yield strength at 900°

C. of 70 Mp or more.