Abstract: Provided are a Ni-based superalloy for stably obtaining high tensile strength and a method for manufacturing the same. Provided are: a Ni-based superalloy having a composition comprising, in mass %, C: up to 0.10%, Si: up to 0.5%, Mn: up to 0.5%, P: up to 0.05%, S: up to 0.050%, Fe: up to 45%, Cr: 14.0 to 22.0%, Co: up to 18.0%, Mo: up to 8.0%, W: up to 5.0%, Al: 0.10 to 2.80%, Ti: 0.50 to 5.50%, Nb: up to 5.8%, Ta: up to 2.0%, V: up to 1.0%, B: up to 0.030%, Zr: up to 0.10%, Mg: up to 0.005%, and the balance of Ni with inevitable impurities, and has a grain orientation spread (GOS) of at least 0.7° as an intragranular misorientation parameter measured by an SEM-EBSD technique; and a method for manufacturing the same.

Abstract: Provided are a Ni-based alloy for hot die having a high high-temperature compressive strength and a good oxidation resistance and being capable of suppressing the deterioration in the working environment and the shape deterioration, and a hot forging die made of the Ni-based alloy for hot die. The Ni-based alloy for hot die comprises, in mass %, W: 7.0 to 15.0%, Mo: 2.5 to 11.0%, Al: 5.0 to 7.5%, Cr: 0.5 to 3.0%, Ta: 0.5 to 7.0%, S: 0.0010% or less, one or two or more selected from rare-earth elements, Y, and Mg in a total amount of 0 to 0.020%, and the balance of Ni with inevitable impurities. In addition to the composition described above, one or two elements selected from Zr and Hf can further be contained in a total amount of 0.5% or less.

Abstract: Provided is a method for manufacturing a hot-forged member, the method enabling efficient hot forging while preventing defects such as cracks even when a poor workability alloy is used as a material to be hot forged. A method for manufacturing a hot-forged member, comprising: a heating step of heating an unheated material for hot forging in a furnace to a hot forging temperature; a heat-resistant insulation material bonding step of bonding a heat-resistant insulation material to at least a part of a surface of a material for forging removed from the furnace to obtain a material to be hot forged; and a hot forging step of compressing a part or all of the material to be hot forged into a predetermined shape using any of a die, an anvil, and a tool.

Abstract: Provided are a Ni-based alloy for hot die having a high high-temperature compressive strength and a good oxidation resistance and being capable of suppressing the deterioration in the working environment and the shape deterioration, and a hot forging die made of the Ni-based alloy for hot die. The Ni-based alloy for hot die comprises, in mass %, W: 7.0 to 15.0%, Mo: 2.5 to 11.0%, Al: 5.0 to 7.5%, Cr: 0.5 to 3.0%, Ta: 0.5 to 7.0%, S: 0.0010% or less, one or two or more selected from rare-earth elements, Y, and Mg in a total amount of 0 to 0.020%, and the balance of Ni with inevitable impurities. In addition to the composition described above, one or two elements selected from Zr and Hf can further be contained in a total amount of 0.5% or less.

Abstract: Provided are a Ni-based superalloy for stably obtaining high tensile strength and a method for manufacturing the same. Provided are: a Ni-based superalloy having a composition comprising, in mass %, C: up to 0.10%, Si: up to 0.5%, Mn: up to 0.5%, P: up to 0.05%, S: up to 0.050%, Fe: up to 45%, Cr: 14.0 to 22.0%, Co: up to 18.0%, Mo: up to 8.0%, W: up to 5.0%, Al: 0.10 to 2.80%, Ti: 0.50 to 5.50%, Nb: up to 5.8%, Ta: up to 2.0%, V: up to 1.0%, B: up to 0.030%, Zr: up to 0.10%, Mg: up to 0.005%, and the balance of Ni with inevitable impurities, and has a grain orientation spread (GOS) of at least 0.7° as an intragranular misorientation parameter measured by an SEM-EBSD technique; and a method for manufacturing the same.

Abstract: Provided are a Ni-based alloy for hot die having a high high-temperature compressive strength and a good oxidation resistance and being capable of suppressing the deterioration in the working environment and the shape deterioration, and a hot forging die made of the Ni-based alloy for hot die. The Ni-based alloy for hot die comprises, in mass %, W: 7.0 to 15.0%, Mo: 2.5 to 11.0%, Al: 5.0 to 7.5%, Cr: 0.5 to 3.0%, Ta: 0.5 to 7.0%, S: 0.0010% or less, one or two or more selected from rare-earth elements, Y, and Mg in a total amount of 0 to 0.020%, and the balance of Ni with inevitable impurities. In addition to the composition described above, one or two elements selected from Zr and Hf can further be contained in a total amount of 0.5% or less.

Abstract: The present invention provides a method for producing a ring-rolled material of an Fe—Ni based superalloy which inhibits AGG, has a fine-grained structure having an ASTM grain size number of at least 8, and has high circularity. A method for producing a ring-rolled material of an Fe—Ni based superalloy having a composition of an Alloy 718 comprises: heating a ring-shaped material for ring rolling having the composition, in a temperature range of 900° C. to 980° C., and performing finishing ring rolling, as a finishing ring rolling step; heating the ring-rolled material that has been subjected to the finishing ring rolling, in a temperature range of 980 to 1010° C.; and correcting ellipticalness while expanding a diameter of the ring-rolled material by using a ring expander.

Abstract: The present invention provides a method for producing a ring-rolled material of an Fe—Ni based superalloy which inhibits AGG, has a fine-grained structure having an ASTM grain size number of at least 8, and has high circularity. A method for producing a ring-rolled material of an Fe—Ni based superalloy having a composition of an Alloy 718 comprises: heating a ring-shaped material for ring rolling having the composition, in a temperature range of 900° C. to 980° C., and performing finishing ring rolling, as a finishing ring rolling step; heating the ring-rolled material that has been subjected to the finishing ring rolling, in a temperature range of 980 to 1010° C.; and correcting ellipticalness while expanding a diameter of the ring-rolled material by using a ring expander.

Abstract: A method for producing a ring-rolled material of an Fe—Ni based superalloy, which has a high circularity, can inhibit AGG, and can inhibit grain growth. A method for producing a ring-rolled material of an Fe—Ni based superalloy having a composition of an Alloy 718 comprises: a finishing ring rolling step of heating a ring-shaped material for ring rolling having the composition, in a temperature range of 900° C. to 980° C., and performing finishing ring rolling; and a circularity correcting step of correcting an ellipticalness of the ring-rolled material that has been rolled in the finishing ring rolling step, while expanding a diameter of the ring-rolled material by using a ring expander including a pipe-expanding cone and a pipe-expanding die, wherein the ring-rolled material that has been rolled in the finishing ring rolling step is subjected to circularity correction without being reheated or after having been heated to up to 960° C.

Abstract: Provided are a Ni-based alloy for hot die having a high high-temperature compressive strength and a good oxidation resistance and being capable of suppressing the deterioration in the working environment and the shape deterioration, a hot forging die using the Ni-based alloy for hot die, and a method for manufacturing a forged product using the hot forging die. The present invention provides a hot forging die comprising a Ni-based alloy for hot die comprising, in mass %, W: 7.0 to 15.0%, Mo: 2.5 to 11.0%, Al: 5.0 to 7.5%, Cr: 0.5 to 7.5%, and the balance of Ni with inevitable impurities, wherein at least 80% of a surface area of the Ni-based alloy for hot die is covered with an aluminum oxide layer. In addition to the composition, the Ni-based alloy for hot die may further comprise 7.0% or less of Ta and may further comprise one or two or more elements selected from Zr: 0.5% or less, Hf: 0.5% or less, rare-earth elements: 0.2% or less, Y: 0.2% or less, and Mg: 0.03% or less.

Abstract: Provided are a Ni-based alloy for hot die having a high high-temperature compressive strength and a good oxidation resistance and being capable of suppressing the deterioration in the working environment and the shape deterioration, and a hot forging die made of the Ni-based alloy for hot die. The Ni-based alloy for hot die comprises, in mass %, W: 7.0 to 15.0%, Mo: 2.5 to 11.0%, Al: 5.0 to 7.5%, Cr: 0.5 to 3.0%, Ta: 0.5 to 7.0%, S: 0.0010% or less, one or two or more selected from rare-earth elements, Y, and Mg in a total amount of 0 to 0.020%, and the balance of Ni with inevitable impurities. In addition to the composition described above, one or two elements selected from Zr and Hf can further be contained in a total amount of 0.5% or less.

Abstract: Provided is a Ni-based alloy for hot forging die having high compressive strength at high temperature and good oxidation resistance that is capable of suppressing work environment deterioration and shape deterioration. A Ni-based alloy for hot forging die in the present invention includes, by mass, 7.0 to 12.0% W, 4.0 to 11.0% Mo, 5.0 to 7.5% Al, and 0.5 to 7.5% Cr, and the balance of Ni with inevitable impurities. In addition, the Ni-based alloy for hot forging die may further include 0.5 to 7.0% by mass Ta and may further include one or more elements selected from, by mass, 0.001 to 0.5% Zr, 0.001 to 0.5% Hf, 0.001 to 0.2% a rare-earth element, 0.001 to 0.2% Y, and 0.001 to 0.03% Mg. The Ni-based alloy for hot forging die may have a 0.2% compressive proof strength of at least 500 MPa at a test temperature of 1000° C. and a strain rate of 10?3/sec.

Abstract: A production method for an Fe—Ni based heat-resistant superalloy inhibits abnormal grain growth and yields a fine crystal grain structure having an ASTM crystal grain size number of 9 or greater. The production method comprises at least a hot working step in which a material having a prescribed composition is subjected to hot working, wherein the hot working step includes at least a step in which the above material of 930 to 1010° C. is subjected to hot working so that the relation of (effective strain)?0.139×(effective strain rate(/sec))?0.30 is satisfied in the entirety of the above material.

Abstract: The present invention provides a high quality material for ring rolling. The material includes radially outer and inner peripheral surfaces. In the material, a center of gravity on a half section is located so as to be closer to the outer peripheral surface in contact with a main roll than a center of the half section in a thickness direction, a shape of the half section includes a height reducing portion having a height from a center line dividing the half section into halves in a height direction, this height is gradually reduced toward the inner peripheral surface in contact with a mandrel roll, and the shape is formed in a substantially linear symmetry such that the center line is a symmetric axis. A height of the inner peripheral surface is from 20% to 50% of a maximum height of the material.

Abstract: There is provided a method of manufacturing an Ni-base superalloy which enables a uniform coat of a glass lubricant to be maintained even after heated to hot forging temperature. The method of manufacturing an Ni-base superalloy in which a forging stock containing an Ni-base superalloy, coated with a lubricant, is subjected to hot forging includes: a preliminary oxidation step of previously generating a Cr oxide coating film having a film thickness of 0.5 to 50 ?m on the forging stock thereby to obtain a preliminarily oxidized material; a lubricant coating step of coating the preliminarily oxidized material with a glass lubricant containing borosilicate glass as a main component thereby to obtain a material to be forged; and a hot forging step of hot forging the material to be forged thereby to obtain a hot forged material.

Abstract: There is provided a method for producing a Ni-based heat-resistant superalloy a primary ?? 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.

Abstract: A high-strength Ni-base alloy having favorable corrosion resistance, high strength, and high ductility, around room temperature is provided. A high-strength Ni-base alloy includes: in % by mass, less than 0.01% of C, not more than 0.5% of Si, not more than 0.5% of Mn, 15 to 25% of Cr. 1.0 to 5.0% of Mo or Mo+0.5W, 0.2 to 0.8% of Al, 1.0 to 2.0% of Ti, 3.00 to 3.80% of Nb, not more than 30% of Fe, and 0.0007 to 0.010% of Mg; Ni; and impurities. A value represented by Mg/S is not less than 0.7, and an A value is not less than 0.015 and less than 0.027, the A value being represented by A value=Al/(Al+1.77(Ti?1.36C)+3.44(Nb?5.1C)).

Abstract: There is provided an Ni-base super alloy which is used for airplane engines and gas turbines for power generation and has favorable mechanical properties at high temperature. The Ni-base super alloy contains 0.001 to 0.1 mass % of C, 1.0 to 4.0 mass % of Al, 2.0 to 4.5 mass % of Ti, 12.0 to 18.0 mass % of Cr, 11.1 to 18.0 mass % of Co, 1.2 to 12.0 mass % of Fe, 1.5 to 6.5 mass % of Mo, 0.5 to 6.0 mass % of W, 0.1 to 3.0 mass % of Nb, 0.001 to 0.05 mass % of B, 0.001 to 0.1 mass % of Zr, and Ni and impurities as a remainder.

Abstract: There is provided a method of manufacturing an Ni-base superalloy which enables a uniform coat of a glass lubricant to be maintained even after heated to hot forging temperature. The method of manufacturing an Ni-base superalloy in which a forging stock containing an Ni-base superalloy, coated with a lubricant, is subjected to hot forging includes: a preliminary oxidation step of previously generating a Cr oxide coating film having a film thickness of 0.5 to 50 ?m on the forging stock thereby to obtain a preliminarily oxidized material; a lubricant coating step of coating the preliminarily oxidized material with a glass lubricant containing borosilicate glass as a main component thereby to obtain a material to be forged; and a hot forging step of hot forging the material to be forged thereby to obtain a hot forged material.

Abstract: There is provided an Ni-base super alloy which is used for airplane engines and gas turbines for power generation and has favorable mechanical properties at high temperature. The Ni-base super alloy contains 0.001 to 0.1 mass % of C, 1.0 to 4.0 mass % of Al, 2.0 to 4.5 mass % of Ti, 12.0 to 18.0 mass % of Cr, 11.1 to 18.0 mass % of Co, 1.2 to 12.0 mass % of Fe, 1.5 to 6.5 mass % of Mo, 0.5 to 6.0 mass % of W, 0.1 to 3.0 mass % of Nb, 0.001 to 0.05 mass % of B, 0.001 to 0.1 mass % of Zr, and Ni and impurities as a remainder.