Abstract: Rhenium-free nickel based alloys are provided. More particularly, the alloys comprise preferred levels and ratios of elements so as to achieve good high temperature strength of both gamma matrix phase and gamma prime precipitates, as well as good environmental resistance, without using rhenium. When cast and directionally solidified into single crystal form, the alloys exhibit creep and oxidation resistance substantially equivalent to or better than rhenium-bearing single-crystal alloys. Further, the alloys can be processed by directional solidification into articles in single crystal form or columnar structure comprising fine dendrite arm spacing, e.g., less than 400 ?m, if need be, so that further improvements in mechanical properties in the articles can be seen.

Abstract: The present invention provides methods for manufacturing an article having a wetting-resistant surface. The method includes providing a mixture comprising a plurality of micron-sized first particles and a plurality of nano-sized second particles, and a binder; depositing the mixture onto a substrate to form a wetting-resistant surface via a thermal spray process. The mixture is deposited without substantial melting of the first and second particles. The wetting-resistant surface has wettability sufficient to generate, with a reference fluid, a static contact angle of greater than about 90 degrees.

Abstract: A method of making a soft magnetic material with fine grain structure is provided. The method includes the steps of providing a soft magnetic starting material; heating the soft magnetic starting material to a temperature at which the material has a microstructure comprising at least two solid phases; and deforming the soft magnetic starting material. An electrical device comprising a magnetic component is provided. The magnetic component comprises a soft magnetic material having a grain size less than about 3 micrometers. The material has a composition that comprises at least two solid phases at temperatures greater than about 500° C.

Abstract: An article made of an alloy, and a method for making the article, are presented. The alloy is substantially free of martensite, and comprises the following composition: at least about 75 weight percent titanium; up to about 10 weight percent of a beta stabilizing component; from about 3 weight percent to about 15 weight percent of an alpha stabilizing component; and from about 0.05 weight percent to about 5 weight percent germanium. Another embodiment is a method for fabricating an article. The method comprises providing a billet made of an alloy as described above, and stabilizing the billet microstructure to form a stabilized billet; the method may further comprise superplastically processing the stabilized billet to form a processed item.

Abstract: A system, in certain embodiments, includes a backing plate, a tungsten-based member disposed along the backing plate, wherein the tungsten-based member defines a welding work surface, and the tungsten-based member comprises curved grooves configured to secure the tungsten-based member to the backing plate. The system also includes a drive. The system includes a pin tool movable by the drive to create friction along one or more workpieces disposed on the welding work surface, wherein the frictional heating and mechanical stirring is configured to create a stir weld along the one or more workpieces. The system, in some embodiments, also may include a backing plate comprising liquid passages and gas passages and a tungsten-based member disposed along the backing plate, wherein the tungsten-based member defines a welding work surface.

Abstract: The present invention provides a friction stir welding apparatus operable for welding one or more metals, metal alloys, or other materials, and a method for friction stir welding. The friction stir welding apparatus includes a pin tool holder, a shoulder having a surface coupled to the pin tool holder, and a pin tool coupled to the pin tool holder, the pin tool at least partially protruding from the surface of the shoulder, wherein the pin tool is made of a consumable pin tool material. The method includes introducing the pin tool into a workpiece; traversing the pin tool along a joint to be welded on the workpiece; and substantially continuously feeding the pin tool into the weld joint as it is traversed along the joint, thereby incorporating at least a portion of the consumable pin tool material into the volume of the joint to be welded.

Abstract: A soft magnetic alloy including iron, cobalt, and at least one alloying addition including a platinum group metal, rhenium, or combinations thereof is provided. A device which is formed from such an alloy is also described.

Abstract: A system, in certain embodiments, includes a backing plate, a tungsten-based member disposed along the backing plate, wherein the tungsten-based member defines a welding work surface, and the tungsten-based member comprises curved grooves configured to secure the tungsten-based member to the backing plate. The system also includes a drive. The system includes a pin tool movable by the drive to create friction along one or more workpieces disposed on the welding work surface, wherein the frictional heating and mechanical stirring is configured to create a stir weld along the one or more workpieces. The system, in some embodiments, also may include a backing plate comprising liquid passages and gas passages and a tungsten-based member disposed along the backing plate, wherein the tungsten-based member defines a welding work surface.

Abstract: A method of coating a substrate with cryo-milled, nano-grained particles includes forming a face-centered-cubic gamma matrix comprising nickel, cobalt, chromium, tungsten and molybdenum, adding a dispersion strengthening material to the gamma matrix to form a first mixture, cryo-milling the first mixture to form a second mixture to form a nano-grained structure, and cold spraying the second mixture onto a substrate to form a coating having a nano-grained structure.

Abstract: A nanocomposite comprising a plurality of nanoparticles dispersed in a molybdenum-based matrix, and an x-ray tube component formed from such a nanocomposite. The nanocomposite contains volume fraction of nanoparticle dispersoids in a range from about 2 volume percent to about 20 volume percent. A method of making such molybdenum-based nanocomposites is also disclosed.

Abstract: A refractory composition is described, containing niobium, silicon, titanium, and at least one of rhenium and ruthenium. The amount of silicon in the composition is at least about 9 atom %, and the amount of titanium present is less than about 26 atom %, based on total atomic percent. Turbine engine components formed from such a composition are also disclosed.

Abstract: A coating suitable for use as protective oxide-forming coatings on Nb-based substrates, and particularly monolithic niobium-based alloys, exposed to high temperatures and oxidative environments. The coating contains aluminum, may further contain silicon, and optionally contains niobium, titanium, hafnium, and/or chromium, which in combination form one or more intermetallic phases that promote the formation of a slow-growing oxide scale. The intermetallic phases may be M(Al,Si)3, M5(Al,Si)3, and/or M3Si5Al2 where M is niobium, titanium, hafnium, and/or chromium.

Abstract: Nb—Si based alloy articles comprising a Nb—Si based alloy upon which is disposed an environmentally-resistant coating are described. They include a coating comprising at least one phase selected from the group consisting of M(Al,Si)3, M5(Al,Si)3, and M3Si5Al2, wherein M is one or more of Nb, Ti, Hf, Cr. Such coating can improve the environmental (e.g., in oxidation-promoting environments) resistance of a Nb—Si based alloy and alloy articles. Methods for preparing these articles are described as well.

Abstract: The present invention provides methods for manufacturing an article having a wetting-resistant surface. The method includes providing a mixture comprising a plurality of micron-sized first particles and a plurality of nano-sized second particles, and a binder; depositing the mixture onto a substrate to form a wetting-resistant surface via a thermal spray process. The mixture is deposited without substantial melting of the first and second particles. The wetting-resistant surface has wettability sufficient to generate, with a reference fluid, a static contact angle of greater than about 90 degrees.

Abstract: An article including a monolithic body including iron, cobalt, and nitrogen is provided. The monolithic body includes a matrix phase and a plurality of particles disposed within the matrix phase. The particles include a phase comprising nitrogen.

Abstract: A nanocomposite comprising a plurality of nanoparticles dispersed in a molybdenum-based matrix, and an x-ray tube component formed from such a nanocomposite. The nanocomposite contains volume fraction of nanoparticle dispersoids in a range from about 2 volume percent to about 20 volume percent. A method of making such molybdenum-based nanocomposites is also disclosed.

Abstract: Niobium silicide articles are described. They include a surface region enriched with at least about 25 atom % germanium, which can enhance the properties of the article. Methods for preparing these articles are described as well. According to one method, an article is formed from a niobium silicide composite material which contains a selected amount of germanium. The article is then heat-treated under conditions sufficient to increase the level of germanium in the surface region to at least about 25 atom %, based on the total composition of the surface region. In another embodiment, a germanium-containing material is applied over a niobium-silicide article, and then diffused into the surface region of the article by way of a heat treatment.

Abstract: The present invention provides methods for manufacturing an article having a wetting-resistant surface. The method includes providing a substrate. The method further includes disposing a coating mixture on a surface of the substrate, wherein the coating mixture comprises a braze material and a texture-providing material. The method further includes heating the braze material to bond the texture-providing material to the surface of the substrate to form the article having the wetting-resistant surface.

Abstract: An article is presented where the article comprises an alloy having a minor phase dispersed within a matrix phase and a plurality of substantially equiaxed grains. The article further comprises a continuous gradient in grain size from a first grain size at an outer surface of the article to a second grain size at an inner portion of the article, wherein the first grain size is less than the second grain size. Methods for forming the article using high deformation processing are also presented, where the processing includes extruding the feedstock material through a die having a twist channel configured to apply a torsional strain to the feedstock material as it passes through the die to form an extruded billet.

Abstract: A metallic structure having a graded microstructure is provided. The metallic structure comprises a graded region comprising a plurality of grains having a gradient in grain size varying as a function of position between a first median grain size at an outer region and a second median grain size at an inner region and a plurality of dispersoids dispersed within the microstructure. The first median grain size is different from the second median grain size. A method of forming a metallic structure having a graded microstructure is also provided. The method comprises: providing a metallic structure comprising at least one reactive species; diffusing at least one reactant at a controlled rate from an outer region of the metallic structure towards an inner region of the metallic structure to form a gradient in reactant activity; reacting the reactant with the reactive species to form a plurality of dispersoids; and heat treating the metallic structure to achieve grain growth so as to form a graded microstructure.