Ni-based heat-resistant superalloy and method for producing the same

Patent metadata

Field	Value
Publication number	US-9903011-B2
Application number	US-201414780230-A
Country	US
Kind code	B2
Filing date	Mar 25, 2014
Priority date	Mar 28, 2013
Publication date	Feb 27, 2018
Grant date	Feb 27, 2018

Abstract

There is provided a method for producing a Ni-based heat-resistant superalloy a primary γ′ phase with an average particle size of at least 500 nm comprising the steps of: providing a material to be hot-worked having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities; heating the material to be hot-worked in a temperature having a range of 1,130 to 1,200° C. for at least 2 hours; cooling the material to be hot-worked heated by the heating step to a hot working temperature or less at a cooling rate of at most 0.03° C./second; and subjecting the material to be hot-worked to hot working after the cooling step.

First claim

The invention claimed is:

1. A method for producing a Ni-based heat-resistant superalloy, the method comprising the steps of:
providing a material to be hot-worked having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities;
heating the material to be hot-worked in a temperature having a range of 1,130 to 1,200° C. for at least 2 hours;
cooling the material to be hot-worked heated by the heating step to a hot working temperature or less at a cooling rate of at most 0.03° C./second; and
subjecting the material to be hot-worked to hot working after the cooling step.

2. The method for producing a Ni-based heat-resistant superalloy according to claim 1 , further comprising a second heating step for heating the material to be hot-worked in a temperature that has a range of 950 to 1,160° C. and is lower than the temperature performed by the first heating step for at least 2 hours after or during the cooling step.

3. The method for producing a Ni-based heat-resistant superalloy according to claim 1 , wherein the material to be hot-worked has a composition consisting of, by mass, 0.005 to 0.04% C, 1.5 to 3.0% Al, 5.5 to 6.7% Ti, 13 to 16% Cr, 20 to 27% Co, 2.0 to 3.5% Mo, 0.7 to 2.0% W, 0.005 to 0.04% B, 0.005 to 0.06% Zr, and the balance of Ni with inevitable impurities.

4. The method for producing a Ni-based heat-resistant superalloy according to claim 1 , wherein the material to be hot-worked has a composition consisting of, by mass, 0.005 to 0.02% C, 2.0 to 2.5% Al, 6.0 to 6.5% Ti, 13 to 14% Cr, 24 to 26% Co, 2.5 to 3.2% Mo, 1.0 to 1.5% W, 0.005 to 0.02% B 0.010 to 0.04% Zr, and the balance of Ni with inevitable impurities.

5. A method for producing a Ni-based heat-resistant superalloy, the method comprising the steps of:
heating an ingot having a composition consisting of, by mass, 0.001 to 0.05% C, 1.0 to 4.0% Al, 4.5 to 7.0% Ti, 12 to 18% Cr, 14 to 27% Co, 1.5 to 4.5% Mo, 0.5 to 2.5% W, 0.001 to 0.05% B, 0.001 to 0.1% Zr, and the balance of Ni with inevitable impurities in a hot working temperature having a range of 800 to 1,125° C. and subjecting the resulting ingot to first hot working at a hot working ratio of 1.1 to 2.5 to provide a hot-worked material;
reheating the hot-worked material in a temperature range that is higher than the temperature performed at the first hot working and is lower than a γ′ phase solvus temperature to provide a reheated material;
cooling the reheated material to a temperature having a range of 700 to 1,125° C. at a cooling rate of at most 0.03° C./second; and
performing second hot working after the cooling step.

6. The method for producing a Ni-based heat-resistant superalloy according to claim 5 , wherein the ingot has a composition consisting of, by mass, 0.005 to 0.04% C, 1.5 to 3.0% Al, 5.5 to 6.7% Ti, 13 to 16% Cr, 20 to 27% Co, 2.0 to 3.5% Mo, 0.7 to 2.0% W, 0.005 to 0.04% B, 0.005 to 0.06% Zr, and the balance of Ni with inevitable impurities.

7. The method for producing a Ni-based heat-resistant superalloy according to claim 5 , wherein the ingot has a composition consisting of, by mass, 0.005 to 0.02% C, 2.0 to 2.5% Al, 6.0 to 6.5% Ti, 13 to 14% Cr, 24 to 26% Co, 2.5 to 3.2% Mo, 1.0 to 1.5% W, 0.005 to 0.02% B, 0.010 to 0.04% Zr, and the balance of Ni with inevitable impurities.

8. The method for producing a Ni-based heat-resistant superalloy according to claim 5 , wherein the temperature for the reheating step has a range of 1,135° C. to 1,160° C.

Assignees

• Hitachi Metals Ltd

Inventors

• Sato Jun
• Kobayashi Shinichi
• Ueno Tomonori
• Ohno Takehiro
• Aoki Chuya
• SHIMOHIRA Eiji

Classifications

• C22C19/056

  with the maximum Cr content being at least 10% but less than 20% · CPC title

• C22C30/00

  Alloys containing less than 50% by weight of each constituent · CPC title

• C22F1/10 Primary

  of nickel or cobalt or alloys based thereon · CPC title

• C22C19/05

  with chromium · CPC title