Abstract: The addition of small amounts of CeO2 and Cr to intermetallic compositions of NiAl and FeAl improves ductility, thermal stability, thermal shock resistance, and resistance to oxidation, sulphidization and carburization.

Abstract: An article protected by a protective coating includes a substrate made of a first nickel-base superalloy substrate material that is susceptible to the formation of a secondary reaction zone when overlaid by a diffusion aluminide coating or an aluminide overlay coating. A protective coating including a deposited coating at the substrate surface. The deposited coating is a second nickel-base superalloy different from the first nickel-base superalloy and which does not produce a secondary reaction zone when interdiffused with the first nickel-base superalloy. In one version, the deposited coating has a nominal composition, in weight percent, of about 3.1 percent cobalt, about 7.6 percent chromium, about 7.8 percent aluminum, about 5.45 percent tantalum, about 3.85 percent tungsten, about 1.65 percent rhenium, about 0.02 percent carbon, about 0.016 percent hafnium, about 0.015 percent boron, about 0.5 percent silicon, balance nickel and incidental impurities.

Abstract: A two step heat treatment for Ni—Cr—Mo alloys containing from 12% to 23.5% chromium provides higher yield strength, high tensile strength and other mechanical properties comparable to those observed in similar alloys age-hardened according to current practices. This treatment is done over a total time of not more than 50 hours. However, the treatment works for only those alloys having alloying elements present in amounts according to an equation here disclosed.

Abstract: A nickel-base superalloy that exhibits outstanding mechanical properties under high temperature and high strain conditions when cast in an equiaxed and/or directionally solidified, columnar grain structure, and which exhibits increased grain boundary strength and ductility while maintaining microstructural stability includes, in percentages by weight, 5-6 chromium, 9-9.5 cobalt, 0.3-0.7 molybdenum, 8-9 tungsten, 5.9-6.3 tantalum, 0.05-0.25 titanium, 5.6-6.0 aluminum, 2.8-3.1 rhenium, 1.1-1.8 hafnium, 0.10-0.12 carbon, 0.010-0.024 boron, 0.011-0.020 zirconium, with the balance being nickel and incidental impurities. The superalloys of this invention are useful for casting gas turbine engine components exhibiting significantly improved low cycle fatigue life, improved airfoil high temperature stress rupture life, significantly reduced life cycle cost, and longer useful life.

Abstract: A low thermal expansion Ni-base superalloy contains, by weight % (hereinafter the same as long as not particularly defined) C: 0.15% or less; Si: 1% or less; Mn: 1% or less; Cr: 5 to 20%; at least one of Mo, W and Re of Mo+½ (W+Re) of 17 (exclusive) to 25%; Al: 0.2 to 2%; Ti: 0.5 to 4.5%; Fe of 10% or less; at least one of B: 0.02% and Zr: 0.2% or less; a remainder of Ni and inevitable impurities; wherein the atomic % of Al+Ti is 2.5 to 7.0.

Abstract: A superalloy weld composition includes: up to about 5.1 wt % Co; about 7.2 to about 9.5 wt % Cr; about 7.4 to about 8.4 wt % Al; about 4.3 to about 5.6 wt % Ta; about 0.1 to about 0.5 wt % Si; about 0.1 to about 0.5 wt % Hf; up to about 0.05 wt % C; up to about 0.05 wt % B; about 0 to about 2.2 Re; about 2.7 to about 4.4 wt % W; and balance Ni and typical impurities.

Abstract: A nickel base super alloy composition wherein the ratio of molybdenum to tungsten or to the sum of tungsten and rhenium, 1 M ⁢   ⁢ o W ⁢   ⁢ o ⁢   ⁢ r , M ⁢   ⁢ o W + R ⁢   ⁢ e

Abstract: An alloy and repair material comprising the alloy, articles comprising the alloy and repair material, and methods for repairing articles including provision of the alloy as repair material are described, with the alloy comprising ruthenium, nickel, aluminum, and chromium, wherein a microstructure of the alloy is essentially free of an L12-structured phase at temperatures greater than about 1000° C. and comprises an A3-structured phase and up to about 40 volume percent of a B2-structured phase.

Abstract: The object of the present invention is to provide an Ni-based single crystal super alloy capable of improving strength by preventing precipitation of a TCP phase at high temperatures. This object is achieved by an Ni-based single crystal super alloy having a composition consisting of 5.0-7.0 wt % Al, 4.0-8.0 wt % Ta, 2.9-4.5 wt % Mo, 4.0-8.0 wt % W, 3.0-6.0 wt % Re, 0.01-0.50 wt % Hf, 2.0-5.0 wt % Cr, 0.1-15.0 wt % Co and 1.0-4.0 wt % Ru in terms of its weight ratio, with the remainder consisting of Ni and unavoidable impurities.

Abstract: A single step heat treatment for Ni—Cr—Mo alloys containing from 12% to 19% chromium and from 18% to 23% molybdenum provides higher yield strength, high tensile strength and other mechanical properties comparable to those observed in similar alloys age-hardened according to current practices. This treatment is done over a total time of at least 24 hours and preferably less than 50 hours. However, the treatment works for only those alloys having alloying elements present in amounts according to an equation here disclosed.

Abstract: Nickel aluminum alloys are welded utilizing a nickel based alloy containing zirconium but substantially free of titanium and niobium which reduces the tendency to crack.

Abstract: A nickel base alloy for high temperature thermal processing hardware requiring ultra-low spallation and metal loss rates in oxidizing and nitriding atmospheres for use in wire mesh belting, thermocouple sheathing, resistive heating elements, heat sensing cables, furnace internals and like hardware. The compositional range of the alloy is 15.0-23.0 % Cr, 0.5-2.0 % Si, 0.0-4.0% Mo, 0.0-1.2 % Nb, 0.0-3.0 % Fe, 0.0-0.5 % Ti, 0.0-0.5 % Al, 0.0-0.3 % Mn, 0.0-0.1 % Zr, 0.0-0.06 % Ce, 0.005-0.025 % Mg, 0.0005-0.005 % B, 0.005-0.3 % C, 0.0-20.0 % Co, balance Ni. The alloy possesses a high degree of hot and cold workability, phase stability and strength retention at elevated temperatures.

Abstract: Burn-resistant metal alloys that also have a high tensile strength are described. The alloys generally include about 55 to about 75 weight percent nickel, about 12 to about 17 weight percent cobalt, about 4 to about 16 weight percent chromium, about 1 to about 4 weight percent aluminum, and about 1 to about 4 weight percent titanium.

Abstract: A two step heat treatment for Ni—Cr—Mo alloys containing from 12% to 23.5% chromium provides higher yield strength, high tensile strength and other mechanical properties comparable to those observed in similar alloys age-hardened according to current practices. This treatment is done over a total time of not more than 50 hours. However, the treatment works for only those alloys having alloying elements present in amounts according to an equation here disclosed.

Abstract: Nickel-based superalloy, suitable for monocrystalline solidification, having the following composition by weight: 1 Co:  4.75 to 5.25% Cr:  15.5 to 16.5% Mo:  0.8 to 1.2% W:  3.75 to 4.25% Al:  3.75 to 4.25% Ti:  1.75 to 2.25% Ta:  4.75 to 5.25% C: 0.006 to 0.04% B: ≦0.01% Zr: ≦0.01% Hf: ≦1% Nb: ≦1% Ni and any impurities: complement to 100%.

Abstract: Nickel-based superalloy, suitable for monocrystalline solidification, having the following composition by weight: 1 Co:  4.75 to 5.25% Cr:  11.5 to 12.5% Mo:  0.8 to 1.2% W:  3.75 to 4.25% Al:  3.75 to 4.25% Ti:    4 to 4.8% Ta:  1.75 to 2.25% C: 0.006 to 0.04% B: ≦0.01% Zr: ≦0.01% Hf: ≦1% Nb: ≦1% Ni and any impurities: complement to 100%.

Abstract: An article, such as a turbine engine component, formed from a nickel-base superalloy, the nickel-base superalloy containing a &ggr;″ tetragonal phase and comprising aluminum, titanium, tantalum, niobium, chromium, molybdenum, and the balance nickel, wherein the article has a time dependent crack propagation resistance of at least about 20 hours to failure at about 1100° F. in the presence of steam. The invention also includes a nickel-base superalloy for forming such and article and methods of forming the article and making the nickel-base superalloy.

Abstract: The present invention relates to an improved single crystal nickel base superalloy and a process for making same. The single crystal nickel base superalloy has a composition comprising 3 to 12 wt % chromium, up to 3 wt % molybdenum, 3 to 10 wt % tungsten, up to 5 wt % rhenium, 6 to 12 wt % tantalum, 4 to 7 wt % aluminum, up to 15 wt % cobalt, up to 0.05 wt % carbon, up to 0.02 wt % boron, up to 0.1 wt % zirconium, up to 0.8 wt % hafnium, up to 2.0 wt % niobium, up to 1.0 wt % vanadium, up to 0.7 wt % titanium, up to 10 wt % of at least one element selected from the group consisting of ruthenium, rhodium, palladium, osmium, iridium, platinum, and mixtures thereof, and the balance essentially nickel. The single crystal nickel base superalloy has a microstructure which is pore-free and eutectic &ggr;-&ggr;′ free and which has a gamma prime morphology with a bimodal &ggr;′ distribution.

Abstract: A superalloy has a composition of, in weight percent, from about 16.0 percent to about 22.4 percent cobalt, from about 6.6 percent to about 14.3 percent chromium, from about 1.4 percent to about 3.5 percent tantalum, from about 1.9 percent to about 4.0 percent tungsten, from about 1.9 percent to about 3.9 percent molybdenum, from about 0.03 percent to about 0.10 percent zirconium, from about 0.9 percent to about 3.0 percent niobium, from about 2.4 percent to about 4.6 percent titanium, from about 2.6 percent to about 4.8 percent aluminum, from 0 to about 2.5 percent rhenium, from about 0.02 percent to about 0.10 percent carbon, from about 0.02 percent to about 0.10 percent boron, balance nickel and minor amounts of impurities. The superalloy is advantageously utilized in aircraft gas turbine disks.

Abstract: The improved filler metal for use in the welding of Ni—Cr—W alloys that are excellent in high-temperature strength and corrosion resistance and which are used in the hot-zone structures of high-temperature gas-cooled reactors, gas turbines, etc comprises on a mass basis C≦0.05%, Mn≦0.1%, Si≦0.1% (Mn+Si≦0.1%), Cr=17-20%, W=20-23% (Cr+W=39-43%), Ti=0.02-0.1%, Zr≦0.03%, Y≦0.015%, B=0.0003-0.01%, Al≦0.1%, Mg≦0.05%, Nb≦0.06% (10Zr+10B+5Nb+2Y≦0.3%), the balance being Ni and incidental impurities.

Abstract: A Ni-base heat resistant alloy excellent in weldability and strength at elevated temperatures and suited for use in manufacturing cracking furnace tubes and reformer furnace tubes to be used in ethylene plants as well as a welded joint therefor is provided. The alloy of the invention is a Ni-base heat-resistant alloy, which comprises C: not more than 0.1%, Si: not more than 2%, Mn: not more than 2%, P: not more than 0.025%, S: not more than 0.005%, N: not more than 0.04%, Cr: 10 to 30%, Al: 2.1 to less than 4.5%, and Mo: 2.5 to 15% or W: 2.5 to 9% or Mo and W: 2.

Abstract: High molybdenum, corrosion-resistant alloys are provided with greatly increased thermal stability by controlling the atom concentrations to be NiaMobXcYdZe, where: a is between about 73 and 77 atom percent b is between about 18 and 23 atom percent X is one or more required substitutional alloying elements selected from Groups VI, VII and VIII of the Periodic Table and c does not exceed about 5 atom percent for any one element, Y is one or more optional substitutional alloying elements which may be present and d does not exceed about one atom percent for any one element, Z is one or more interstitial elements and e is as low as possible, not exceeding about 0.2 atom percent in total; and the sum of c and d is between about 2.5 and 7.5 atom percent.

Abstract: A nickel base alloy for high temperature thermal processing hardware requiring ultra-low spallation and metal loss rates in oxidizing and nitriding atmospheres for use in wire mesh belting, thermocouple sheathing, resistive heating elements, heat sensing cables, furnace internals and like hardware. The compositional range of the alloy is 15.0-23.0% Cr, 0.5-2.0% Si, 0.04.0% Mo, 0.0-1.2% Nb, 0.0-3.0% Fe, 0.0-05% Ti, 0.0-0.5% Al, 0.0-0.3% Mn, 0.0-0.1% Zr, 0.0-0.035% Ce, 0.005-0.025% Mg, 0.0005-0.005% B, 0.005-0.3% C, 0.0-20.0% Co, balance Ni. The alloy possesses a high degree of hot and cold workability, phase stability and strength retention at elevated temperatures.

Abstract: A high strength, corrosion resistant Cr—Co—Ni base alloy for long-life service at 530° C. to 820° C. containing in % by weight about 23.5-25.5% Cr, 15.0-22.0% Co, 0.2-2.0% Al, 0.5-2.5% Ti, 0.5-2.5% Nb, up to 2.0% Mo, up to 1.0% Mn, 0.3-1.0% Si, up to 3.0% Fe, up to 0.3% Ta, up to 0.3% W, 0.005-0.08% C, 0.01-0.3 % Zr, 0.001-0.01% B, up to 0.05% rare earth as misch metal, 0.005-0.025% Mg plus optional Ca, balance Ni including trace additions and impurities. The alloy provides a combination of strength, ductility, stability, toughness and oxidation/sulfidation resistance so as to render the alloy range uniquely suitable for engineering applications where oxygen/sulfur-containing atmospheres are life limiting, in applications such as exhaust valves for diesel engines and in tubes for coal-fired steam boilers.

Abstract: A nickel-based alloy for producing, by casting, components which have solidified in single crystal form, contains rhenium and tungsten, as well as aluminium, chromium and cobalt. The rhenium content is at least 2.3% by weight, and the weight ratio of the tungsten content to the rhenium content is at least 1.1 to at most 1.6.

Abstract: A Ni3Al alloy with improved weldability is described. It contains about 6-12 wt % Al, about 6-12 wt % Cr, about 0-3 wt % Mo, about 1.5-6 wt % Zr, about 0-0.02 wt % B and at least one of about 0-0.15 wt % C, about 0-0.20 wt % Si, about 0-0.01 wt % S and about 0-0.30 wt % Fe with the balance being Ni.

Abstract: A turbine disk for a gas turbine engine differentially heat treated so as to produce a dual property disk. The process is applicable to superalloy disks, and achieves substantially uniform yet different temperatures in the rim and hub of the disk during heat treatment, so as to attain specific and different properties for the rim and hub. The process includes the steps of heat treating the entire disk to achieve a uniform structure having a fine grain size and fine precipitates. A device for heating the rim of the disk is then disposed at the disk's periphery, such that the rim is maintained at a substantially uniform temperature above the gamma prime solvus temperature of the superalloy so as to dissolve gamma prime precipitates present in the rim and cause grain growth in the rim.

Abstract: An Ni-based or Ni—Co-based heat-resistant alloy wire excellent in resistance to sag at high temperatures ranging from 600 to 700° C., which excellent resistance is most suitable for spring materials. The heat-resistant alloy wire contains (a) 0.01 to 0.40 wt % C, 5.0 to 25.0 wt % Cr, and 0.2 to 8.0 wt % Al; (b) at least one constituent selected from the group consisting of 1.0 to 18.0 wt % Mo, 0.5 to 15.0 wt % W, 0.5 to 5.0 wt % Nb, 1,0 to 10.0 wt % Ta, 0.1 to 5.0 wt % Ti and 0.001 to 0.05 wt % B; (c) at least one constituent selected from the group consisting of 3.0 to 20.0 wt % Fe and 1.0 to 30.0 wt % Co; and (d) the remaining constituent consisting mainly of Ni and unavoidable impurities. The wire has (a) a tensile strength not less than 1,400 N/mm2 and less than 1,800 N/mm2, (b) an average crystal-grain diameter not less than 5 &mgr;m and less than 50 &mgr;m in a cross section, and (c) a crystal-grain aspect ratio (a major-axis/minor-axis ratio) of 1.2 to 10 in a longitudinal section.

Abstract: A nickel-base superalloy that is useful for making single crystal castings exhibiting outstanding stress-rupture properties, creep-rupture properties, and an increased tolerance for grain defects contains, in percentages by weight, from about 4.3% to about 5.3% chromium, (Cr), from about 9% to about 10% cobalt (Co), from about 0.6% to about 0.8% molybdenum (Mo), from about 8.4% to about 8.8% tungsten (W), from about 4.3% to about 4.8% tantalum (Ta), from about 0.6% to about 0.8% titanium (Ti), from about 5.6% to about 5.8% aluminum (Al), from about 2.8% to about 3.1% rhenium (Re), from about 0.9% to about 1.5% hafnium (Hf), from about 0.06% to about 0.08% carbon (C), from about 0.012% to about 0.020% boron (B), from about 0.004% to about 0.010% zirconium (Zr), the balance being nickel and incidental impurities.

Abstract: An oxidation-resistant coating is described, formed of an alloy containing: about 40 to about 50 atom % aluminum and about 0.5 atom % to about 3 atom % tantalum; with a balance of nickel; cobalt, iron, or combinations thereof. The coating may also include chromium and a precious metal, as well as other components, such as zirconium or molybdenum. A method for applying the oxidation-resistant coating to a substrate is also described. The substrate can be formed of superalloy material, e.g., a turbine engine component. Related articles are also disclosed.

Abstract: A high-temperature component made of a nickel super-alloy has the following composition in wt %: 11-13% of Cr, 3-5% of W, 0.5-2.5% of Mo, 3-5% of Al, 3-5% of Ti, 3-7% of Ta, 1-5% of Re and a remainder formed of nickel. A corresponding component which is also provided is formed of an alloy having a composition essentially similar to that mentioned above, but with the rhenium proportion replaced with 0.1-5 wt % of ruthenium.

Abstract: The invention relates to a coating which contains large volumetric fractions, preferably from 20 to 90% by volume, of NiAl-&bgr; phase in a &ggr; matrix. It contains the following microalloying elements which increase the ductility of the coating (data in % by weight): 0.1-8 Fe and/or 0.1-8 Mo and/or 0.1-8 Ga, where the total Fe, Mo and Ga content is at most 10%. In addition, small amounts of Zr, C and/or B may be added to the alloy, strengthening the &bgr;/&ggr; phase boundaries.

Abstract: A nickel base super alloy composition wherein the ratio of molybdenum to tungsten or to the sum of tungsten and rhenium, Mo w ⁢   or , Mo w + Re Is in the range of about 0.25 to about 0.5 weight percent.

Abstract: A superalloy weld composition, includes: about 2 to about 5 wt % Co; about 5 to about 15 wt % Cr; about 7 to about 10 wt % Al; about 4 to about 6 wt % Ta; about 0.5 to about 1.5 wt % Si; about 0.1 to about 0.5 wt % Hf; up to about 0.05 wt % C; up to about 0.05 wt % B; about 1.0 to about 2.0 Re; about 3 to about 4.5 wt % W; and balance Ni.

Abstract: A heat resistant Ni base alloy comprises, on a mass% basis, 0.1% or less C, 2% or less Si, 2% or less Mn, 0.005% or less S, 10 to 25% Cr, 2.1 to less than 4.5% Al, 0.08% or less N, 0.001 to 1% in total of one or more elements of B: 0.03% or less, Zr: 0.2% or less and Hf: 0.8% or less, and 2.5 to 15% in total of one or more elements of Mo: 0.01 to 15% and W: 0.01 to 9%. The alloy is suitable as a material for a pipe used in ethylene cracking furnace.

Abstract: Nickel-based alloy useful for welding, welding method, and welding electrode.

Abstract: A manufacturing method, particularly a heat treatment method of a Ni-based alloy having sulfidation-corrosion resistance used for component members of corrosion-resistant high-temperature equipment, that is, Waspaloy (a trademark of United Technologies) or its improved Ni-based alloy wherein the high temperature sulfidation-corrosion resistance of the alloy can be improved while maintaining hot strength properties is disclosed. A Ni-based alloy used for the method consists essentially of 0.005 to 0.1% C, 18 to 21% Cr, 12 to 15% Co, 3.5 to 5.0% Mo, not more than 3.25% Ti and 1.2 to 4.0% Al (expressed in mass percentage), with the balance substantially comprising Ni. In the manufacturing method of a Ni-based alloy having improved sulfidation-corrosion resistance, the alloy is, after solution heat treatment, subjected to stabilizing treatment at a temperature not lower than 860° C. and not higher than 920° C. for 1 to 16 hours, and aging treatment at a temperature not lower than 680° C.

Abstract: An article is formed of a single crystal having a composition, in weight percent, of a modifying element in an amount of from about 0.2 to about 2.0 percent by weight hafnium, from about 0.1 to about 0.5 percent by weight zirconium, or combinations thereof, and a base alloy composition of from about 4 to about 20 percent cobalt, from about 1 to about 10 percent chromium, from about 5 to about 7 percent aluminum, from 0 to about 2 percent molybdenum, from about 3 to about 8 percent tungsten, from about 4 to about 12 percent tantalum, from 0 to about 2 percent titanium, from 0 to about 8 percent rhenium, from 0 to about 6 percent ruthenium, from 0 to about 1 percent niobium, from 0 to about 0.1 percent carbon, from 0 to about 0.01 percent boron, from 0 to about 0.1 percent yttrium, and balance nickel and incidental impurities.

Abstract: A nickel-base superalloy, in particular for the production of single-crystal components or directionally solidified components, comprising (measured in % by weight): 3.0-13.0% Cr, 5.0-15.0% Co, 0-3.0% Mo, 3.5-9.5% W, 3.2-6.0% Al, 0-3.0% Ti, 2.0-10.0% Ta, 0-6.0% Re, 0.002-0.08% C, 0-0.04% B, 0-1.4% Hf, 0-0.005% Zr, 10-60 ppm N, remainder nickel plus impurities. As a result of the addition of nitrogen in defined quantities, TiN is formed during solidification and carbides with a block morphology are formed. It is thus possible to increase the carbon content without deterioration in the low cycle fatigue at high load temperature.

Abstract: The localized pitting tendency of castable nickel-base superalloys in a high-temperature corrosive environment is suppressed without loss of desirable hot corrosion resistance, mechanical properties or microstructural stability characteristics by displacement of molybdenum and tungsten in the carbide phase to the matrix through the addition to the alloy of a comparatively small amount of tantalum, columbium or hafnium.

Abstract: A process for forging large components of Alloy 718 material so that the components do not exhibit abnormal grain growth includes the steps of: a) providing a billet with an average grain size between ASTM 0 and ASTM 3; b) heating the billet to a temperature of between 1750° F. and 1800° F.; c) upsetting the billet to obtain a component part with a minimum strain of 0.125 in at least selected areas of the part; d) reheating the component part to a temperature between 1750° F. and 1800° F.; e) upsetting the component part to a final configuration such that said selected areas receive no strains between 0.01 and 0.125; f) solution treating the component part at a temperature of between 1725° F. and 1750° F.; and g) aging the component part over predetermined times at different temperatures. A modified process achieves abnormal grain growth in selected areas of a component where desirable.

Abstract: A composition comprises cobalt; chromium; carbon; boron; zirconium; aluminum; at least one refractory material; and nickel. The composition is used as a repair material for repairing superalloy articles in a repair process.

Abstract: A nickel-based superalloy includes from 1.4 to 4.4 wt. % of Cr, from 3 to 8 wt. % of Co, from 5 to 7.5 wt. % of W, from 4.8 to 7.5 wt. % of Re, from 6 to 9 wt. % of Ta, from 4.8 to 6 wt. % of Al, from 0.1 to 0.5 wt. % of Nb, from 0.8 to 1.8 wt. % of Hf, from 0.05 to 0.1 wt. % of C, from 0.01 to 0.05 wt. % of Y, from 0.005 to 0.15 wt. % of B, and balance Ni.

Abstract: A nickel-base alloy containing a continuous matrix composed of a solid solution of chromium in nickel and a precipitate granularly dispersed in and coherent with the matrix and composed of an intermetallic nickel compound. The intermetallic nickel compound contains gallium that replaces aluminum and/or titanium partly or completely. The invention also relates to an article of manufacture containing a substrate formed of such a nickel-base alloy.

Abstract: A nickel base superalloy comprising 14.0 to 20.0 wt % cobalt, 13.5 to 17.0 wt % chromium, 2.5 to 4.0 wt % aluminium, 3.4 to 5.0 wt % titanium, 0 to 3.0 wt % tantalum, 3.8 to 5.5 wt % molybdenum, 0.035 to 0.07 wt % carbon, 0.01 to 0.04 wt % boron, 0.055 to 0.075 wt % zirconium, 0 to 0.4 wt % hafnium and the balance nickel plus incidental impurities. The nickel base superalloy is suitable for use as gas turbine engine high pressure compressor rotor discs or turbine discs. It is capable of operation at temperatures above 700° C. and has good fatigue crack propagation resistance, creep resistance and tensile strength.

Abstract: Compositional requirements and processing improvements are disclosed which improve the hydrogen embrittlement resistance and the fatigue resistance in air of nickel base single crystal articles. The compositional requirements enlarge the difference between the &ggr;′ solvus temperature and the incipient melting temperature, thus enabling the solution of &ggr;/&ggr;′ eutectic islands without causing incipient melting, while hot isostatic pressing and careful melt practice eliminate porosity and carbides, borides and nitrides, all of which act as crack initiation sites.

Abstract: A low thermal expansion Ni-base superalloy contains, by weight % (hereinafter the same as long as not particularly defined), C: 0.15% or less; Si: 1% or less; Mn: 1% or less; Cr: 5 to 20%; at least one of Mo, W and Re of Mo+½ (W+Re) of 10 to 25%; Al: 0.2 to 2%; Ti: 0.5 to 4.5%; Fe of 10% or less; at least one of B: 0.02% and Zr: 0.2% or less; a remainder of Ni and inevitable impurities; wherein the atomic % of Al+Ti is 2.5 to 7.0.

Abstract: A single crystal casting is cast from a nickel base superalloy including Cr, Co, Mo, W, Ta, Al, Ti, Re and Hf as alloying elements with C increased effective to substantially reduce formation of a solidification-driven, as-cast eutectic/secondary phase scale metallurgically bonded to the casting when the alloy is cast as a single crystal and to reduce recrystallized grains when the casting is solution heat treated.

Abstract: A die cast article such is composed of nickel base superaloy IN 718 is disclosed. The microstructure is characterized by an absence of flowlines and includes a fine average grain size, e.g., ASTM 3 or smaller. Exemplary articles include gas turbine engine components, such as blades, vanes, cases and seals.

Abstract: An Ni-base heat resistant alloy, has a composition which contains, by weight, Cr: from 12.0 to 14.3%, Co: from 8.5 to 11.0%, Mo: from 1.0 to 3.5%, W: from 3.5 to 6.2%, Ta: from 3.0 to 5.5%, Al: from 3.5 to 4.5%, Ti: from 2.0 to 3.2%, C: from 0.04 to 0.12%, B: from 0.005 to 0.05%, and the balance substantially Ni and inevitable impurities. A large-size casting, as well as a large-size turbine blade, having a columnar crystalline Ni-base heat-resistant alloy formed from the Ni-base heat-resistant alloy, have sound cast surfaces and a sound internal structure.