General Electric Company

Michael F Gigliotti, Jr

Melvin Robert Jackson

Shyh-Chin Huang

Andrew Philip Woodfield

Charles D Greskovich

Swe-Wong Yang

Mark Gilbert Benz

Ann Melinda Ritter

Robert S Gilmore

Russell Scott Miller

Russell W Smashey

Lee Cranford Perocchi

Charles A Bruch

Kenneth J Meltsner

Michael F Henry

Mark Daniel Gorman

Eric Allen Ott

Clifford Earl Shamblen

John R Hughes

Steven A Miller

Liang Jiang

Edward James Nieters

Raymond Alan White

John R Rairden, Iii

Thomas F Sawyer

Huang Shyh-Chin

Brian J Marquardt

David A Woodford

Sherwin S Yang

Xuan Nguyen-Dinh

Richard A Amato

Romgopal Darolia

Mark L Prugar

Ernest Leroy Hall

A metallic article is prepared by first furnishing at least one nonmetallic precursor compound, wherein all of the nonmetallic precursor compounds collectively containing the constituent elements of the metallic article in their respective constituent-element proportions. The constituent elements together form a titanium-base alloy having a stable-oxide-forming additive element therein, such as magnesium, calcium, scandium, yttrium, lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, and lutetium, and mixtures thereof. The stable-oxide-forming additive element forms a stable oxide in a titanium-based alloy. At least one additive element is present at a level greater than its room-temperature solid solubility limit in the titanium-base alloy. The precursor compounds are chemically reduced to produce an alloy material, without melting the alloy material. The alloy material may be consolidated. The alloy material, or consolidated metallic article, is thereafter desirably exposed to an oxygen-containing environment at a temperature greater than room temperature.

Method for producing a titanium-base alloy having an oxide dispersion therein

A modified platinum group metal coating composition comprising a phase having a solid solution face-centered cubic (fcc) crystal structure, rich in platinum group materials. In order to be effective, the platinum group metal coating material was modified based on the chemical composition and chemical activity of the substrate material. The platinum group metal coating material was modified to include, in solid solution, elements of the superalloy substrate, specifically nickel (Ni) and cobalt (Co). Depending on the substrate material, the modified platinum group metal coating material may not even include Ni or Co, but may be modified to include amounts of different elements that are consistent with the chemical composition of the substrate. The modified platinum metal coating material also includes aluminum (Al). The composition may include small amounts of a second phase isolated within the fcc phase matrix.

Platinum group bond coat modified for diffusion control

An apparatus for sorting fragments of titanium-based sponge on the basis of color is disclosed. The apparatus captures at least one color image of each fragment, inserts relevant color values from the image into an automated color-sorting system to determine the color of the fragment, and segregates the fragments according to color or range-of-color, by way of a physical segregation apparatus controlled by the color sorting system. The color sorting systems usually involve the conversion of color images from the fragments into color signals, which are in turn transformed into color values. The color images are usually represented by a pattern of pixels. The color values are automatically compared to values, which are part of a look-up table based on data sets, which embrace acceptable or rejectable color values. Comparison of color values determined for the fragments with those in the look-up table results in the acceptance or rejection of each fragment.

Apparatus for color-based sorting of titanium fragments

A bond coat (20) of a thermal barrier coating system for components designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The composition of the bond coat (20) has graded thermal expansion properties that moderate the transition between a metal substrate (10) and a thermal-insulating ceramic layer (12) of a TBC protecting the substrate (10), while also reducing the service temperature of the bond coat (20) so as to reduce its rate of oxidation. Preferably, the bond coat (20) has multiple layers (20a, 20b, 20c), with the coefficients of thermal conductivity of the individual bond coat layers (20a, 20b, 20c) being very close to that of the substrate (10) in order to promote heat transfer from the outward layer (20c) of the bond coat (20) to the substrate (10). By minimizing the service temperature of the bond coat (20) while grading the thermal expansion properties through the coating system, a more spall-resistant coating system is achieved. The inward layer (20a) of the bond coat (20) preferably contains a metallic constituent, such as an aluminum and/or chromium-containing intermetallic, MCrAl and/or MCrAlY, a middle layer (20b) of the bond coat (20) also contains the metallic constituent in addition to a chromium phase, and an outward layer (20c) of the bond coat (20) contains the chromium phase and at least one platinum-containing phase. The middle and outermost layers (20b, 20c) may also contain chromium carbides such as Cr.sub.3 C.sub.2.

Graded bond coat for a thermal barrier coating system

A method for sorting fragments of titanium-based sponge on the basis of color is disclosed. The method involves the steps of capturing at least one color image of each fragment, inserting relevant color values from the image into an automated color-sorting system to determine the color of the fragment, and segregating the fragments according to color or range-of-color, by way of a physical segregation apparatus controlled by the color sorting system. A related apparatus for sorting moving fragments of titanium-based sponge on the basis of color is also described.

Method and apparatus for color-based sorting of titanium fragments

A bond coat of a thermal barrier coating system for components designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The composition of the bond coat has graded thermal expansion properties that moderate the transition between a metal substrate and a thermal-insulating ceramic layer of a TBC protecting the substrate, while also reducing the service temperature of the bond coat so as to reduce its rate of oxidation. Preferably, the bond coat has multiple layers, with the coefficients of thermal conductivity of the individual bond coat layers being very close to that of the substrate in order to promote heat transfer from the outward layer of the bond coat to the substrate. By minimizing the service temperature of the bond coat while grading the thermal expansion properties through the coating system, a more spall-resistant coating system is achieved.

Additions of a first alloy constituent of at least one element from the group consisting of Y, Sc, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu, or any combinations of them, and a second alloy constituent of at least one element from the group consisting of C, Si, Ge, Sn and Pb, or any combinations of them, to Ti-base alloys can be employed so as to result in an alloy containing an very fine, substantially homogeneous oxide dispersoid of the first constituent, and produce alloys having improved tensile properties, especially tensile elongation. The dispersoid results from the decomposition of an intermediate phase dispersoid comprising a compound of the first and second constituents which results from rapid solidification of the alloy from a melt. It is preferred that the second alloy constituent should be at a concentration sufficient to form the intermediate phase with all of the element or elements comprising the first alloy constituent.

Titanium alloys having refined dispersoids and method of making

A hollow article is made by providing and diffusion bonding the opposing parts of an article made of an alpha-beta titanium alloy. Hydrogen is introduced into the surface of an internal cavity before, during, or after diffusion bonding. The article is heat treated with the hydrogen present, typically by solution treating and aging the hydrogen-containing bonded article. The result is the production of a microstructure at the internal surface of the cavity that is resistant to fatigue-crack initiation, while retaining a microstructure throughout the rest of the article that is resistant to fatigue-crack propagation. After heat treating, the hydrogen Is removed from the article, and any further heat treating and other operations are completed.

Fatigue-resistant hollow articles

A hollow article is made by providing and diffusion bonding the opposing parts of an article made of an alpha-beta titanium alloy. Hydrogen is introduced into the surface of an internal cavity before, during, or after diffusion bonding. The article is heat treated with the hydrogen present, typically by solution treating and aging the hydrogen-containing bonded article. The result is the production of a microstructure at the internal surface of the cavity that is resistant to fatigue-crack initiation, while retaining a microstructure throughout the rest of the article that is resistant to fatigue-crack propagation. After heat treating, the hydrogen is removed from the article, and any further heat treating and other operations are completed.

Manufacture of fatigue-resistant hollow articles

A nondestructive evaluation method is described for ultrasonic evaluation and detection of features in polycrystalline materials, such as grain orientation (e.g. texturing) or grain boundary orientation. The method may, for example, be employed to detect diffusion bonds that contain undesirable planar grain boundary arrays. The method utilizes time of flight statistics gathered from reflections associated with incident ultrasonic signals directed into a plurality of locations within the material.

Method for ultrasonic evaluation of materials using time of flight

A method of heat treating Ti/Al-base alloys to improve tensile ductility and reduce the likelihood of in-service embrittlement is disclosed. The method comprises: selecting a Ti/Al-base alloy that contains a mixture of .alpha. and .alpha.2 phases, heat treating the alloy so as to form a controlled amount of .alpha.2 particles, and then cooling the alloy so as to primarily promote the growth of additional .alpha.2 on the previously formed particles, rather than the nucleation of new .alpha.2 particles. This method may be used with Ti/Al-base alloys that also comprise Sn, Ga and In as alloy constituents, and is believed to be useful for a number of Ti/Al-base engineering alloys. Alloys made by this method have been observed to maintain significant tensile ductility, even after aging at elevated temperatures under load (e.g. creep conditions).

Method for heat treating Ti/Al-base alloys

A method of making metal alloy articles having inclusions which are predetermined and controlled with respect to their size, shape, composition, crystal structure and location and orientation within the article is disclosed. In a preferred embodiment, the method of making is directed toward titanium alloy articles containing synthesized hard-alpha inclusions of titanium/nitrogen, titanium/oxygen and titanium/oxygen/nitrogen alloys.

Method of making alloy standards having controlled inclusions

Titanium alloys containing aluminum, hafnium, tantalum, and silicon are found to have improved tensile strengths as well as ductility and oxidation resistance at temperatures up to and above 750.degree. C. without embrittlement.

High strength oxidation resistant titanium base alloy

A method for improved atomization of molten metal having a melting point above 1000.degree. C. is taught. The atomization is carried out in close coupled atomizer. The melt to be atomized is supplied from a reservoir where it is heated to a temperature slightly above the melting point. The molten metal from the reservoir is guided to the atomization zone by a ceramic melt guide tube. The atomization is accomplished with the aid of a shallow draft atomizing nozzle. The melt in the melt guide tube is heated with the aid of an induction coil which is disposed thereabout and between the reservoir and the shallow draft gas nozzle.

Integral induction heating of close coupled nozzle

Enhanced crystallographic texture is developed in an alpha or alpha-beta titanium alloy having a dispersion of particles therein, by heating the alloy to essentially the all beta phase range and mechanically hot working the alloy in this range. The mechanical working is preferably accomplished by extrusion, rolling, or forging. The particles are stable during working, and prevent the formation of random texture in recrystallized beta phase grains at the working temperature. The particles are preferably oxides formed from rare earth elements such as erbium or yttrium, that are introduced into the alloy during manufacture. The alloys processed according to the invention are preferably prepared by powder metallurgy to achieve a uniform microstructure prior to working. A particularly suitable alpha-beta (but near alpha) titanium alloy contains aluminum, zirconium, hafnium, tin, columbium, molybdenum, tungsten, ruthenium, germanium, silicon, and erbium.

Growing community of inventors

Scotia, NY, United States of America

Michael F Gigliotti, Jr