Abstract: A method for the diffusion bonding of a graphite member to a metallic surface of molybdenum, molybdenum alloy, tungsten or tungsten alloy as part of a composite rotary anode for an X-ray tube is set forth. In the completed structure a crack-free compound laminate separating and joining the graphite member and the metallic surface comprises a layer of carbide of metal of the metallic surface bonded to a layer of platinum or platinum alloy.
Abstract: It has been found that tri-nickel aluminide compositions are quite sensitive to the ratio of nickel to aluminum in their ability to receive boron as a dopant and that compositions which are relatively poor in the aluminum component can be doped more effectively with boron. Further, it has been found for the nickel aluminides which have lower concentrations of aluminum that the percentage of boron which can be added to the composition to effectively increase the strength of the alloys is favored by the lower aluminum ratio so that higher concentrations of boron are addable. The compositions which result have significant strength properties based on tensile tests of the compositions.
Type:
Grant
Filed:
September 4, 1984
Date of Patent:
February 10, 1987
Assignee:
General Electric Company
Inventors:
Alan I. Taub, Shyh-Chin Huang, Keh-Minn Chang
Abstract: A method for the diffusion bonding of a graphite member to a metallic surface as part of a composite rotary anode for an X-ray tube is set forth. In the completed structure a compound laminate separating and metallurgically bonded to the graphite member and to the metallic surface consists of, in sequence, a layer comprising carbide of vanadium and of a metal selected from the group consisting of molybdenum and tungsten, a layer of metal selected from the group consisting of vanadium and vanadium alloys, a zone of interdiffused metals comprising platinum and vanadium and then a continuous layer comprising platinum or platinum alloy.
Abstract: An apparatus for atomization of high temperature melts to from very finely divided powder. The apparatus has a ceramic central melt delivery tube. Melt is introduced at the top and exits at the bottom. At the exit surface a high velocity gas impinges on the melt to atomize the melt into fine particles. The bottom portion of the melt delivery tube has an internal shape to expand the external configuration of the melt stream.
Abstract: An oxygen sensor having increased stability in its sensitivity is provided. The oxygen sensor includes a sensing electrode spaced from a cadmium counter electrode. An alkaline electrolyte extends between the electrodes and permits the formation of cadmium hydroxide in the counter electrode as the cell is used. An electrical circuit connects the counter electrode and sensing electrode externally of the cell. The circuit includes a resistor and thermistor network and a voltmeter. Readings on the voltmeter can be calibrated to show the concentration of ambient oxygen diffusing a polymer membrane to the sensor electrode.
Abstract: A method for generating prime powder from a material having a high melting point and apparatus for generating the powder is taught. The apparatus includes a melt delivery tube. The melt of the high melting material is introduced into the tube and exits from the tube into an atomization zone. Gas is delivered to the zone at high pressure as a stream to atomize the melt. Pursuant to the present invention, the atomizing gas is directed against the lower end of the melt delivery tube and it is deflected from the melt delivery tube into contact with the descending high temperature melt. A concave surface is provided on the end of the melt delivery tube to deflect the gas along the tube surface to minimize Eddy currents and provide better control of the atomization process.
Abstract: High pressure sodium lamps have been subject to progressive reduction in pressure of contained sodium with attendant reduction in lighting quality. It has now been discovered that modification of lamp components permits the pressure of contained sodium to be maintained at higher levels. Emission materials enclosed within the lamp are altered to limit reactive oxygen in the lamp atmosphere. A thermionic electrode is equipped with an improved emission mix composition as illustrated in areas A and B of the triaxial plot of FIG. 3 and an oxygen getter is intermixed with the mix composition. The oxygen getter is a metal which forms a highly stable oxide and may be at least one selected from the group consisting of titanium, zirconium, hafnium, tantalum and yttrium.
Abstract: High pressure sodium lamps have been subject to progressive reduction in pressure of contained sodium with attendant reduction in lighting quality. It has now been discovered that modification of lamp components permits the pressure of contained sodium to be maintained at higher levels. Emission materials enclosed within the lamp are altered to limit reactive oxygen in the lamp atmosphere. A thermionic electrode is equipped with an improved emission mix composition containing an oxide selected from the group consisting of tungsten, molybdenum and yttrium. The emission mix also contains the metal of the respective oxide in finely divided form.
Abstract: High pressure sodium lamps have been subject to progressive reduction in pressure of contained sodium with attendant reduction in lighting quality. It has been discovered that modification of lamp components permits the pressure of contained sodium to be maintained at higher levels. Emission materials enclosed within the lamp are altered to limit reactive oxygen in the lamp atmosphere. A thermionic electrode as equipped with an improved emission composition as illustrated in areas B and C of the triaxial plot of FIG. 3.
Abstract: A tri-nickel aluminide base composition is provided which has good ductility at all temperatures. The composition has a relatively high concentration of cobalt substituent and is doped by boron. It also has minor concentrations of at least two other substituent metals selected from the group consisting of niobium, hafnium, vanadium, molybdenum and zirconium.
Type:
Grant
Filed:
October 3, 1985
Date of Patent:
September 23, 1986
Assignee:
General Electric Company
Inventors:
Keh-Minn Chang, Shyh-Chin Huang, Alan I. Taub
Abstract: Improvements in the strength of atomized and consolidated boron doped tri-nickel aluminides are made possible. The improved strength is achieved by cold rolling and annealing a HIPped aluminide. The improvements are to room temperature properties.
Type:
Grant
Filed:
October 3, 1985
Date of Patent:
September 23, 1986
Assignee:
General Electric Company
Inventors:
Keh-Minn Chang, Shyh-Chin Huang, Alan I. Taub
Abstract: Three-dimensional diode arrays have been produced in semiconductor wafers by a two-step process involving laser drilling and solid-state diffusion.Holes are first produced in the wafer in various arrays by laser drilling. Under suitable conditions, laser drilling causes little or no damage to the wafer. Cylindrical P-N junctions are then formed around the laser-drilled holes by diffusing an impurity into the wafer from the walls of the hole. A variety of distinctly different ISFET devices is produced.
Abstract: A method is taught for rendering a boron-doped tri-nickel aluminide resistant to mechanical failure while at intermediate temperatures of 600.degree. C. to 800.degree. C. due to a hot-short phenomena. The method involves incorporating between 0.05 and 0.30 of cobalt in the composition according to the expression(Ni.sub.1-x-z Co.sub.x Al.sub.z).sub.100-y B.sub.y.The concentration of aluminum, z, is between 0.23 and 0.25 and the concentration of boron, y, is between 0.2 and 1.50 atomic percent. The composition is formed into a melt and the melt is rapidly solidified by atomization and consolidated. The consolidation may be simultaneous with the rapid solidification, as in spray forming, or sequential by atomization to a powder and consolidation of the powder by HIPping. The consolidated body is cold worked to increase the resistance of the body to failure at intermediate temperatures and may be annealed following the cold working.
Type:
Grant
Filed:
October 3, 1985
Date of Patent:
September 2, 1986
Assignee:
General Electric Company
Inventors:
Keh-Minn Chang, Shyh-Chin Huang, Alan I. Taub
Abstract: Inhibition of grain size growth in a tri-nickel aluminide is achieved by additions of minor amounts of a metal selected from the group comprising rhenium and molybdenum.
Type:
Grant
Filed:
September 4, 1984
Date of Patent:
August 19, 1986
Assignee:
General Electric Company
Inventors:
Shyh-Chin Huang, Keh-Minn Chang, Alan I. Taub
Abstract: A method of forming a generally planar part for a jet engine is provided. The part is adapted for withstanding high thermal stress but not high mechanical stress. A preformed strip of a superalloy is mounted around a drum shaped mandrel. A low pressure plasma deposit of a different superalloy is formed on the preformed strip. The strip is demounted and mechanically straightened.
Type:
Grant
Filed:
May 30, 1985
Date of Patent:
August 5, 1986
Assignee:
General Electric Company
Inventors:
Paul A. Siemers, Melvin R. Jackson, Stephen F. Rutkowski
Abstract: Three-dimensional diode arrays have been produced in semiconductor wafers by a two-step process involving laser drilling and solid-state diffusion.Holes are first produced in the wafer in various arrays by laser drilling. Under suitable conditions, laser drilling causes little or no damage to the wafer. Cylindrical P-N junctions are then formed around the laser-drilled holes by diffusing an impurity into the wafer from the walls of the hole. A variety of distinctly different ISFET devices is produced.
Abstract: A method for fabricating junction field-effect transistors includes forming in an N-type silicon substrate a plurality of high-aspect-ratio bores interposed between a source region and a drain region in the substrate, diffusing P-type impurities a predetermined distance into the substrate from the inner surface to each bore to form a concentric, P-type gate zone around each bore, forming electrical contacts to the source and drain regions and to the gate zones and forming a P-type isolation zone surrounding the source and drain regions and the gate zones. The bores, which are preferably formed by laser drilling, extend completely or partially through the thickness of the substrate. The gate zones extend, either completely through the thickness of the substrate or from the top surface of the substrate to a layer-like P-type zone formed adjacent to the bottom surface thereof.
Abstract: A method of melt extraction of titanium alloys is provided. The alloys are those containing a high concentration of titanium and a significant amount of an alloying element selected from the group consisting of molybdenum, tantalum and columbium. Surprisingly, the extraction process is rendered feasible when the surface of the extracting mechanism is of molybdenum.
Type:
Grant
Filed:
October 29, 1984
Date of Patent:
May 20, 1986
Assignee:
General Electric Company
Inventors:
Francis X. Gigliotti, Jr., Lee C. Perocchi, Peter G. Frischmann
Abstract: Substantially homogeneous, substantially spherical interdiffused metallic oxide particles, especially useful in plasma spraying applications, are readily and economically prepared from constituent metal oxide powders by the method of this invention which includes the step of heating a mass of discrete agglomerated particles under conditions of temperature and time sufficient to interdiffuse the constituent metallic oxides within the agglomerates, but insufficient to sinter the agglomerates together.