Provided are a Ni-based heat resistant superalloy for aircraft engine cases excellent in high-temperature characteristic such as tensile characteristics and low-cycle fatigue characteristics in a high-temperature range and also excellent in workability, and an aircraft engine case formed of the same. The Ni-based heat resistant superalloy has composition containing, by mass, Co: 4.0 to 11.0%, Cr: 12.0 to 17.0%, Al: 2.0 to 4.0%, Ti: 2.0 to 4.0%, Al+Ti: 4.6 to 6.7%, Mo: more than 5.5 to 10.0%, W: more than 0 to 4.0%, B: 0.001 to 0.040%, C: 0.02 to 0.06%, Zr: 0 to 0.05%, Mg: 0 to 0.005%, P: 0 to 0.01%, Nb: 0 to 1.0%, Ta: 0 to 1.0%, and Fe: 0 to 2.0%, and the balance of Ni with inevitable impurities, and is suitable for aircraft engine cases.

An austenitic alloy based on nickel and having a high chromium content, intended to be used at a given operating temperature between 900° C. and 1150° C., comprises the following elements by mass percentage: chromium between 40% and 45%; iron between 10% and 14%; carbon between 0.4% and 0.6%; titanium between 0.05% and 0.2%; niobium between 0.5% and 1.5%; at least one reactive element, selected from rare earths or hafnium, between 0.002% and 0.1%; silicon between 0% and 1%; manganese between 0% and 0.5%; nickel to balance the alloy elements. In addition, the alloy has a molar fraction of more than 0.1% of secondary carbo-nitrides rich in niobium and/or titanium, after the operating temperature has been applied thereto. The disclosure also relates to a method for designing such an alloy and to a method for validating such an alloy.

An austenitic alloy based on nickel and having a high chromium content, intended to be used at a given operating temperature between 900° C. and 1150° C., comprises the following elements by mass percentage: chromium between 40% and 45%; iron between 10% and 14%; carbon between 0.4% and 0.6%; titanium between 0.05% and 0.2%; niobium between 0.5% and 1.5%; at least one reactive element, selected from rare earths or hafnium, between 0.002% and 0.1%; silicon between 0% and 1%; manganese between 0% and 0.5%; nickel to balance the alloy elements. In addition, the alloy has a molar fraction of more than 0.1% of secondary carbo-nitrides rich in niobium and/or titanium, after the operating temperature has been applied thereto. The disclosure also relates to a method for designing such an alloy and to a method for validating such an alloy.

A part includes a substrate made of a nickel-based superalloy, the substrate having a first average mass fraction of one or more first elements chosen from hafnium, silicon and chromium, the substrate having an open cavity in the part and a cooling channel, the substrate further including a surface layer partially forming the cavity, the surface layer having a second average mass fraction of the first element or first elements which is greater than the first average mass fraction.

Inventive techniques for forming unique compositions of matter are disclosed, as well as various advantageous physical characteristics, and associated properties of the resultant materials. In particular, metal(s) (including various alloys, such as Inconel superalloys) are characterized by having carbon disposed within the metal lattice structure thereof. The carbon is primarily, or entirely, present at interstitial sites of the metal lattice, and may be present in amounts ranging from about 15 wt % to about 90 wt %. The carbon, moreover, forms non-polar covalent bonds with both metal atoms of the lattice and other carbon atoms present in the lattice. This facilitates substantially homogeneous dispersal of the carbon throughout the resultant material, conveying unique and advantageous properties such as strength-to-weight ratio, density, mechanical toughness, sheer strength, flex strength, hardness, anti-corrosiveness, electrical and/or thermal conductivity, etc. as described herein. In some approaches, the composition of matter may be powderized, or the powder may be pelletized.

Provided is a clad welded pipe or tube that has improved pipe or tube mechanical properties by reducing the width of a weld without its function as a clad pipe or tube being impaired. A clad welded pipe or tube comprises: a first layer made of base metal; and a second layer placed on one surface of the first layer, and made of first cladding metal that is a material different from the base metal, wherein a pipe or tube circumferential length L1 of weld metal at a pipe or tube inner surface and a pipe or tube circumferential length L2 of the weld metal at a pipe or tube outer surface in a weld are each 0.0010 mm or more and 1.0 mm or less, and the base metal is not exposed at a first cladding metal-side surface of the clad welded pipe or tube in the weld.

The present invention provides an alloy for overlay welding with which an alumina barrier layer containing an Al oxide can be formed on a projection that is overlay welded on an inner surface of a reaction tube, and a reaction tube having a projection that is overlay welded on the inner surface as a stirring member. An alloy for overlay welding according to the present invention is an alloy for overlay welding that is to be used in overlay welding, and the alloy contains C in an amount of 0.2 mass % to 0.6 mass %, Si in an amount of more than 0 mass % to 1.0 mass %, Mn in an amount of more than 0 mass % to 0.6 mass % or less, Cr in an amount of 25 mass % to 35 mass %, Ni in an amount of 35 mass % to 50 mass %, Nb in an amount of 0.5 mass % to 2.0 mass %, Al in an amount of 3.0 mass % to 6.0 mass %, Y in an amount of 0.005 mass % to 0.05 mass %, wherein Y/Al is 0.002 or more to 0.015 or less; and the balance being Fe and inevitable impurities.

A nickel-based alloy composition consisting, in weight percent, of: 1.5 to 4.5% aluminium, 1.1 to 3.4% titanium, 0.0 to 4.0% niobium, 0.0 to 5.2% tantalum, 0.9 to 6.6% tungsten, 0.0 to 3.0% molybdenum, 0.0 to 24.0% cobalt, 12.5 to 20.6% chromium, 0.02 to 0.15% carbon, 0.001 to 0.015% boron, 0.0 to 0.1% zirconium, 0.0 to 3.0% rhenium, 0.0 to 2.0% ruthenium, 0.0 to 3.0% iridium, 0.0 to 0.5% vanadium, 0.0 to 1.0% palladium, 0.0 to 1.0% platinum, 0.0 to 0.5% silicon, 0.0 to 0.1% yttrium, 0.0 to 0.1% lanthanum, 0.0 to 0.1% cerium, 0.0 to 0.003% sulphur, 0.0 to 0.25% manganese, 0.0 to 0.1 magnesium, 0.0 to 5.0% iron, 0.0 to 0.5% copper, 0.0 to 1.0% hafnium, the balance being nickel and incidental impurities, wherein the following equations are satisfied in which W.sub.Al, W.sub.Ti, W.sub.Nb, W.sub.Ta and W.sub.W are the weight percent of aluminium, titanium, niobium, tantalum and tungsten in the alloy respectively 0.65≤0.3 W.sub.Nb+0.15 W 3.6≤W.sub.Al+0.5 W.sub.Ti+0.3 W.sub.Nb+0.15 W.sub.Ta≤5.7 W.sub.Ta+0.92W.sub.W≤6.1.

A nickel-based alloy composition consisting, in weight percent, of: 1.5 to 4.5% aluminium, 1.1 to 3.4% titanium, 0.0 to 4.0% niobium, 0.0 to 5.2% tantalum, 0.9 to 6.6% tungsten, 0.0 to 3.0% molybdenum, 0.0 to 24.0% cobalt, 12.5 to 20.6% chromium, 0.02 to 0.15% carbon, 0.001 to 0.015% boron, 0.0 to 0.1% zirconium, 0.0 to 3.0% rhenium, 0.0 to 2.0% ruthenium, 0.0 to 3.0% iridium, 0.0 to 0.5% vanadium, 0.0 to 1.0% palladium, 0.0 to 1.0% platinum, 0.0 to 0.5% silicon, 0.0 to 0.1% yttrium, 0.0 to 0.1% lanthanum, 0.0 to 0.1% cerium, 0.0 to 0.003% sulphur, 0.0 to 0.25% manganese, 0.0 to 0.1 magnesium, 0.0 to 5.0% iron, 0.0 to 0.5% copper, 0.0 to 1.0% hafnium, the balance being nickel and incidental impurities, wherein the following equations are satisfied in which W.sub.Al, W.sub.Ti, W.sub.Nb, W.sub.Ta and W.sub.W are the weight percent of aluminium, titanium, niobium, tantalum and tungsten in the alloy respectively 0.65≤0.3 W.sub.Nb+0.15 W 3.6≤W.sub.Al+0.5 W.sub.Ti+0.3 W.sub.Nb+0.15 W.sub.Ta≤5.7 W.sub.Ta+0.92W.sub.W≤6.1.

A nickel base superalloy powder for additive manufacturing applications is disclosed. The alloy powder has the following broad weight percent composition:

TABLE-US-00001 C   0-0.1 Mn 0.5 max. Si   0-0.03 Cr  4-16 Fe   0-1.5 Mo 0-6 W 0-8 Co  0-15 Ti 0-2 Al 0.5-5.5 Nb 0-6 Ta  7.5-14.5 Hf   0-2.0 Zr   0-0.1 Re 0-6 Ru 0-3 B   0-0.03
The balance of the alloy is at least 50% nickel and the usual impurities. An article of manufacture made from the alloy is also disclosed.