Abstract: A molten metal pump having an elongated shaft with an impeller disposed adjacent the end of the shaft and a means for rotating the shaft. The impeller is formed with an imperforate substantially circular base surrounded by a bearing and has a surface facing toward the shaft. At least two imperforate vanes are connected to and extend substantially perpendicular from the surface and radially from the shaft or a hub securing the shaft toward a peripheral portion of the base. The vanes are spaced apart at terminal inlet ends along their entire radial dimension to create an inlet area comprised of the axial opening between adjacent vanes at the terminal ends and an outlet area comprised of a radial opening between adjacent vanes along the axial direction of the vanes. Each vane has a leading edge with a distal portion adjacent the periphery of the base portion which forms an angle of less than about 100.degree. relative to a tangent to said circular base drawn at the center of the vane.

Abstract: A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed therebetween. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. And, a pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade.

Abstract: An improved abrasive blade tip for gas turbine engines is taught, wherein an abrasive tip coating is applied to the blade tip in such a manner as to lessen wear through of the abrasive and the underlying airfoil on the leading and trailing edges, by coating the blade tip with abrasive not only on the tip surface per se, but so as to cover portions of the convex and concave airfoil surfaces at the corners where the tip surface intersects the leading and trailing edges.

Abstract: A coated article is prepared by melting and casting an article substrate formed of a nickel-base superalloy. The article substrate is heated in a hydrogen-containing atmosphere at a temperature of at least 2000.degree. F. for a period sufficient to desulfurize the substrate to a sulfur content of less than about 1 part per million. Optionally, an aluminum-oxide environmental coating is provided overlying the substrate. A ceramic thermal barrier coating is applied overlying the substrate. Significantly, there being no bond coat applied to the substrate prior to the application of the thermal barrier coating.

Abstract: To manufacture a turbine wheel having blades made of a ceramic or composite material and inserted into a metal hub, firstly blades (16) are manufactured that are right cylindrical, each blade having a base (18) through which a hole is formed; a cylindrical ring (20) is formed, the ring being provided with orifices through which the bases (18) of the respective blades (16) are inserted; the blade bases (18) are successively threaded onto an open annular rigid metal wire (30); the resulting assembly (16, 20, 30) is disposed inside a sealed housing (161); hot isostatic compaction is performed so as to compact a metal alloy in powder form (41) inside the sealed housing (161) so as to make the hub of the turbine wheel (100) while embedding the blade bases (18) and the metal wire (30) by using the powder metallurgy technique; and the outside portion of the sealed housing (161) delimiting the hub of the turbine wheel (101) is machined. Application, in particular, to the field of aeronautical or space engineering.

Abstract: A compressor or turbine blade having its tip coated with a zirconium-based oxide having a plurality of macrocracks extending at least 100 microns through the coating and the process used to produce such a coating.

Abstract: A metallic component of a gas-turbine installation is formed of a nickel-based base material and at least two coating layers superimposed on the base material for improving corrosion-resistance thereof. The coating layers include a first layer having a composition and/or thickness for resisting corrosive attack of the nickel-based base material at temperatures of 600.degree. C. to 800.degree. C. (HTCII), and a second coating layer having a composition and/or thickness for resisting corrosive attack of the base material at temperatures of 800.degree. C. to 900.degree. C. (HTCI).

Abstract: Metal alloy fan blades reinforced with a metal matrix composite for enhancing stiffness of the fan blades without a significant weight penalty, and which are suitable for use in high bypass turbofan engines. The metal matrix composite is bonded to each fan blade near its root so as to increase stiffness and thereby provide frequency and stability control to the fan blades. As a result, a lower engine weight can be realized by using more fan blades without the need for a part span shroud.

Abstract: A process for producing a turbine rotor using an ingot in which segregation is prevented effectively when ESR is used to produce a large-sized ingot. A hole is formed along an axial direction in the core of an electrode. The molten pool is made shallow and flat and segregation is prevented from occurring. Consequently, an ESR ingot of good quality offering an excellent surface is obtainable as it is free from segregation. Moreover, an electrode melting rate is increased and efficiency is improved so that a high quality turbine can be manufactured from the ingot.

Abstract: An impeller for a high-temperature gas blower suitable for a floating conveyor furnace, having vanes each formed of a dispersion-strengthened alloy which includes as a disperse or internal phase 0.1-2.0% by weight of finely divided particles of an oxide of a high melting-point metal, such as Y.sub.2 O.sub.3, Ce.sub.2 O.sub.3, ZrO.sub.2, Al.sub.2 O.sub.3 and Gd.sub.2 O.sub.3, preferably dispersed in an austenite matrix or external phase of Cr, Fe, Al, Ti and Ni. A gas blower having such impeller, and a furnace using such gas blower are also disclosed.

Abstract: A method and apparatus for increasing blade fatigue strength in a turbine engine. The blades in the turbine engine are configured so as to reduce stress at the tip of the blades during operation of the turbine engine, thus increasing blade fatigue strength. This stress reduction helps to counteract the detrimental effect of abrasive tip coatings on blade fatigue strength. In one embodiment, the tip of the blade is chamfered in order to reduce the stress on the tip of the blade. An abrasive coating is then applied to the tip of the blade to assist the blade in seating into an abradable outer air seal. In another embodiment, an abrasive coating is applied to a center portion of the tip of the blade, with the periphery of the abrasive coating being set back from the opposing surfaces of the blade.

Abstract: A molten metal pump including a vaned impeller having a larger outlet area than inlet area which demonstrates prolonged high effectiveness and reduces the likelihood of catastrophic failure.

Abstract: A coated article comprises a base article having a substrate made of a material selected from the group consisting of a nickel-base alloy and a cobalt-base alloy, an intermediate metallic coating structure, and a thermal barrier coating. The intermediate metallic coating structure may be a protective layer of platinum, rhodium, or palladium on the base article, with no bond coat. The intermediate metallic coating may also be a bond coat, either oxidized or unoxidized, with a protective layer of platinum, rhodium, or palladium thereon. The protective layer typically partially interdiffuses with the underlying metallic structure.

Abstract: A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine wheel includes a pair of side walls having a groove formed therebetween and a pair of axially aligned holes radially positioned therein. The turbine blade has a root portion having a bore positioned therein. A pin having a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade is positioned within the axially aligned holes and the bore attaches the blade to the turbine wheel.

Abstract: A turbine blade, preferably used in the low pressure stages of a steam turbine, is formed from a basic titanium alloy. Near the blade tip, it has a region, including the blade leading edge with a surface of a material which is more resistant to erosion than the basic titanium alloy.This turbine blade should be simple to manufacture and should have a long life even under difficult operating conditions.This is achieved in that the region including the blade leading edge has a protective layer formed by surface treatment of the basic titanium alloy by means of a high-power energy source, such as, in particular, a laser.

Abstract: A high efficiency exhauster which is capable of attaining operating efficiencies of up to 70% when employed in a solid fuel pulverizer firing system that includes a pulverizer which is operative to effect the pulverization therewithin of the solid fuel supplied thereto and a furnace into which the pulverized solid fuel is injected for combustion therewithin. The high efficiency exhauster includes a casing, an inlet ring supported on the casing, a rotor mounted on the casing for rotation therewithin, a multiplicity of blades, each of a preestablished length and width, mounted in spaced relation one to another on the circumference of the rotor so as to extend at a preestablished angle, and an outlet formed in the casing.

Abstract: An abrasive medium suitable for the cutting tip of a turbine blade of a gas turbine engine comprises cubic boron nitride grit coated with a layer of aluminum nitride. Coating of the grit particles is carried out by vapour deposition in a fluidised bed reaction.

Abstract: A turbomolecular pump comprises a casing having an inlet port at one end portion and an outlet port at another end portion, a rotor supported rotatably within the casing, and a stator fixed on an inner wall of the casing. The rotor has rotor vanes which coact with stator vanes on the stator to pump gas molecules from the inlet port to the outlet port. The rotor and stator vanes are arranged in multi-steps and have ceramic surfaces at the steps near the outlet port of the casing and have metallic surface at all other steps, so as to promote the baking efficiency and obtain extremely high vacuums.

Abstract: A thermal barrier coating for metal articles subjected to rapid thermal cycling includes a metallic bond coat deposited on the metal article, at least one MCrAlY/ceramic layer deposited on the bond coat, and a ceramic top layer deposited on the MCrAlY/ceramic layer. The M in the MCrAlY material is Fe, Ni, Co, or a mixture of Ni and Co. The ceramic in the MCrAlY/ceramic layer is mullite or Al.sub.2 O.sub.3. The ceramic top layer includes a ceramic with a coefficient of thermal expansion less than about 5.4.times.10.sup.-6 .degree.C.sup.-1 and a thermal conductivity between about 1 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1 and about 1.7 J sec.sup.-1 m.sup.-1 .degree.C.sup.-1.

Abstract: A system for protecting against erosion the surface of a body which is subjected to an airflow and consists essentially of a fibrous material or a fiber-reinforced plastic material, such as a rotor blade, has a metallic coating which, in the respective area to be protected, covers the surface in several layers. The primary layer of the coating consists of aluminum or a similar material with a modulus of elasticity that is approximately identical to that of the material on the surface of the body. The primary layer, in the form of a sheet glued to the surface, is coated with a two-phase material, in which particles of metallic oxide and/or metallic carbide and/or metallic nitride compounds are embedded in a finely distributed manner in a ductile, solid-solution-hardened matrix of a metallic but non-ferrous material.

Abstract: A coating of india-stabilized zirconia protects a self-supporting substrate from high temperatures, as well as vanadate and sulfate corrosion. In one method of making such a protected substrate, a coating of india-stabilized zirconia is applied to the substrate. The substrate can be a metal or ceramic surface of a gas turbine or other type of engine.

Abstract: A stirrer having a complete enamel coating suitable for mounting in a closed coverless reaction vessel, being provided with paddles which are detachably fixed on the shaft for operation inside the vessel by an enamel to enamel coupling obtained by simple pressure without the use of gaskets.

Abstract: A gas turbine having internally cooled thermal barrier coated turbine blades is disclosed. The turbine blades are made from an alloy substrate exhibiting a low coefficient of thermal expansion, an intermediate bond coating and an exterior ceramic coating. Cooling fluid is supplied from the shaft of the compressor where it flows into and out of the turbine blade. Thermal barrier coated turbine blades result in more efficient gas turbine designs.

Abstract: The invention provides an improved combined body of ceramics and metal which maintains high anti-torsional strength and anti-slip off strength while stress concentration is relaxed and deterioration of the ceramics is well prevented. The combined body includes a ceramic member inserted into and firmly engaged with a recess or an opening of a metal member. The combined body has a treated surface region in the vicinity of an engagement end of a contact surface of either the ceramic member or the metal member, and an untreated surface region at a location other than the vicinity of the engagement end.

Abstract: An abrasive system and a processing procedure is provided which permits the direct installation of a thick abrasive blade tip cap onto a cast single crystal turbine rotor blade during a single heating schedule requiring only one furnace operation. The composition of the abrasive blade tip cap advantageously utilizes the high temperature performance capabilities of the single crystal alloy without significantly affecting its mechanical properties as a consequence of the processing necessary to permanently bond the abrasive blade tip cap to the rotor blade. A semi-rigid blade tip cap preform is first formed and positioned on the tip of the rotor blade. The preform and rotor blade are then heated in a vacuum furnace according to a temperature schedule entailing heating rates, holding temperatures and durations which are sufficient to bond and consolidate the preform. The rotor blade is then rapidly cooled in the vacuum furnace to retain the single crystal structure of the rotor blade.

Abstract: A thermal barrier coating system for high temperature superalloys includes an intermetallic bond coating on the substrate and a ceramic topcoat having a columnar grain structure with the columnar axis perpendicular to the surface of the coating. The intermetallic coating is preferably a nickel aluminide or a platinum aluminide, whose upper surface is oxidized during processing to form a thin layer of predominantly aluminum oxide. The ceramic topcoat is preferably zirconium oxide having from about 6 to 20 percent yttrium oxide.

Abstract: A gas turbine bucket and a gas turbine nozzle applied with a ceramic coating comprises a base material of the bucket and the nozzle made of a heat resisting alloy; a plurality of coating layers for the front portion consisting of, a mixture layer which comprises a ceramic material and metal and which is formed on the base material, an alloy layer which comprises an alloy material exhibiting excellent resistance to high temperature oxidation and corrosion and which is formed on the mixture layer, and a ceramic layer which comprises ceramic material and formed on the alloy layer. Such ceramic coating has a satisfactory thermal barrier effect on the base material of the gas turbine bucket and nozzle.

Abstract: The wheel (10), which is made from a composite material having a ceramic matrix comprises a hub that bears a drive gear (16) formed of teeth (20) that extend radially on one of the wheel's surfaces (10a). Each tooth is asymmetrical with respect to the meridian plane (21) that passes through its apex, and has first shoulder (20b) that subtends an angle a, preferably between 15.degree. and 45.degree., relative to that plane, and a second shoulder (20c) that subtends an angle b, preferably between 55.degree. and 85.degree., relative to that plane. Advantageously, the sum of the two angels is at least equal to 100.degree.. The turbine wheel has an improved resistance against inter-laminar shear stresses that result from tightening to a drive gear wheel.

Abstract: A ceramic protective coating system and process for applying the same is provided for superalloy base metal turbine components which are subjected to elevated exhaust temperatures and which exist in a corrosive fluid environment due to the use of fuels which form corrosive compounds upon combustion. The ceramic overcoat consists of at least one protective magnesium titanate of the group MgTiO.sub.3 and Mg.sub.2 TiO.sub.4.

Abstract: A ceramic turbo charger rotor having a blade portion including a shroud tip portion and a top portion, a back plate portion arranged rear of the blade portion, and a shaft portion arranged to the back plate portion is manufactured by working only a part of a back plate portion as a standard surface or by working only a top surface of the tip portion as a standard surface while no working is applied for the back plate portion, so as to reduce a total manufacturing cost.

Abstract: A turbocharger for an automotive vehicle includes a rotatable shaft having a cup-shaped section to which an axial projection of a turbine wheel is fitted under a shrinkage fit. The rotatable shaft is rotatably supported by ball bearings. A nut is screwed on the rotatable shaft in a manner to clamp the ball bearings together with a compressor wheel between the nut and the cup-shaped section. The inner race of the ball bearing on the turbine wheel side is in axially tight contact with an abutting surface formed in the rotatable shaft. In this arrangement, a setting is made to satisfy the following formula. l/P.gtoreq.0.002 where l is a distance (mm) in the rotatable shaft, between a bottom inner surface of the cup-shaped section and the abutting surface; and P is an axial tensile force developed by screwing up the nut in the direction of the cup-shaped section.

Abstract: Ceramic turbine wheels are balanced to minimize rotational vibrations by bonding silica-based glass pads to the wheel. The pads are formed from a mixture of sodium silicate, water and a fine ceramic powder, preferably of a composition similar to the underlying ceramic turbine wheel. The weighted pads are machined, without damage to the underlying ceramic wheel, to achieve proper balance.

Abstract: A ceramic matrix composite article having a varying thickness is fabricated by a process wherein multiple prepreg sheets comprising reinforcing fibers and powdered matrix material are stacked to provide a multi-layer prepreg stack wherein, through each cross-sectional dimension perpendicular to the plane of the sheets, the number of prepreg sheets contributing to the aggregate sheet thickness of the stack varies in proportion to the relative thickness desired in the layered article. The stack may consolidated to a composite article with a smoothly varying thickness profile without undue fiber breakage or ply wrinkling in the composite structure consolidated into a composite article having a smoothly varying thickness profile with reduced internal fiber bowing or breakage. Preferably, the exterior surfaces of the article comprise long, substantially continuous fibers and are free of ply drops.

Abstract: This invention relates to abrasive layers for use in the gas turbine industry. The preferred embodiment of the invention comprises nickel coated, yttria doped silicon nitride particulates dispersed within a nickel base superalloy matrix which is substantially free of oxides. The layer is formed using low pressure plasma spray processes.

Abstract: A turbomachine having a unitary ceramic rotating assembly mounted within a split housing. The rotating assembly includes at least a turbine and integral shaft, the shaft providing a cooled bearing support surface for a fluid film foil bearing.

Abstract: A sacrificial metallic undercoat is provided between the surface of the gas turbine engine stainless steel compressor blade and a protective overcoat of ceramic material.

Abstract: A ceramic-metal joined composite body including a ceramic member having a projection formed thereon, and a metallic member having a recess formed therein. The projection of the ceramic member is fitted into the recess of the metallic member, and a corner of a bottom of the recess has a rounded dimension such that R/D.gtoreq.0.04, in which R and D are the rounded dimension of the corner of the bottom of the recess and an outer diameter of the projection, respectively. The ceramic-metal joined composite body particularly is useful in a rotary shaft for a turbocharger rotor or a gas turbine rotor.

Abstract: A ceramic jointed body composed of two molded bodies which are individually molded by different methods, respectively, and integrally jointed by isostatic pressing, wherein a difference between "amounts of spring back" of the two molded bodies satisfies the formula ##EQU1## thereby preventing cracks from occurring in the jointed body.

Abstract: In heat-connection between metal and ceramic, martensite stainless steel or martensite heat-resistant steel which can be hardened a gas or vacuum after having been heated beyond the quenching temperature thereof are used as metal. The heat connection is brazing or shrinkage fit at 800.degree. C. or more. Stress strain caused by a difference in thermal expansion coefficient between the two can be reduced. Further, since the metal can be connected to ceramic while hardening the metal, man-hour can be reduced markedly.

Abstract: A rotor blade is for a gas turbine engine having a plurality of rotor blades and a substantially coaxial shroud encompassing the tips of the blades. A ceramic layer is bonded to the blade tip, the ceramic layer consisting of a combination of aluminum oxide and zirconium oxide or at least partially stabilized zirconium oxide. The ceramic layer is formed as a plasma sprayed coating or a high velocity oxy-fuel sprayed coating.

Abstract: A radial flow turbine rotor comprises a trunconical shaft and a plurality of blades provided on the periphery of the shaft and inclined to the axis of the shaft. The shaft and the blades are integrally formed of ceramics. The profile of the cross section of each blade, taken along a line perpendicular to the axis of the shaft, is straight between the tip and base of the blade. The tip of each blade is 1.2 to 2.0 mm thick, and each blade grows thicker from the tip toward the base.

Abstract: A high temperature turbine engine includes a rotor portion having axially stacked adjacent ceramic rotor parts. A ceramic/ceramic joint structure transmits torque between the rotor parts while maintaining coaxial alignment and axially spaced mutually parallel relation thereof despite thermal and centrifugal cycling.

Abstract: A high temperature turbine engine includes a hybrid ceramic/metallic rotor member having ceramic/metal joint structure. The disclosed joint is able to endure higher temperatures than previously possible, and aids in controlling heat transfer in the rotor member.

Abstract: Joined ceramic and metal is characterized by ceramic and metal thermally joined through an intermediate layer. The intermediate layer is composed of 20-70% by weight of silver, 1-20% by weight of palladium, 10-60% by weight of nickel and 1-10% by weight of titanium. The joined ceramic and metal has sufficient joining strength both at normal temperature and at high temperature, because the joined ceramic and metal suffers little deterioration even at high temperature. Since the joined ceramic and metal has the characteristics of ceramic such as resistance to heat, corrosion and wear, it can be used for a structure operated at high temperature such as a gas turbine engine, a turbo charger rotor, a piston, a suction valve, and an exhaust valve.

Abstract: A joint structure for joining a ceramic member to a metallic member where the two members have substantially cylindrical end portions. The end portions are place in an abutting relationship and joining member adherent to both connect the two members. A sleeve member covers the joint and is affixed at least to the surface of the end portion of the device having a composition most like the sleeve member. Where the sleeve member is metallic, the surface of the sleeve member is affixed to the metallic portion of the device.

Abstract: A mechanical part has a metal main body and a ceramic tip having a joining surface at which it is joined to the metal main body. The ceramic tip has a chamferred edge at the periphery of the joining surface. The joining surface and the chamferred edge are metallized prior to joining of the joining surface to the metal main body.

Abstract: Ceramic and metal shafts are joined at their ends by brazing, with a buffer member being interposed therebetween. The joined ends of the ceramic and metal shafts and the buffer member are received within a metal sleeve and joined by brazing to part of the inner circumferential wall of the metal sleeve in such a manner than an axial end of the joint where the inner circumferential wall is securely joined to the ceramic and metal shafts is positioned between opposite axial ends of the metal sleeve and at the same time between opposite axial ends of the ceramic shaft. The outer circumferential wall of the metal sleeve is formed with an annular groove in the place corresponding to the above mentioned axial end of the joint with respect to the axial direction of the metal sleeve.

Abstract: A fitting assembly having a ceramic piece fitted to a cup-shaped metal piece filled with solder. Through the use of the difference in thermal expansion coefficients of ceramics and certain metals, an assembly for properly gripping the ceramic by the metal cup is created.

Abstract: Composite bodies comprise a metallic member and a ceramic member integrally joined together by joining a projection of the ceramic member to a recess of the metallic member. Their joining strength is improved by substantially limiting brazing metal to an interface between the outer peripheral surface of the projection of the ceramic member and the innner peripheral surface of the recess of the metallic member. The joining strength is also improved by forming a groove around the outer periphery of the metallic member at the joined end. The joining strength is also improved by providing a space or an intermediate member between a tip end surface of the projection and a bottom surface of the recess and attaining the relation: ##EQU1## in which G, L.sub.1, .alpha., .alpha.', T.sub.S and T.sub.

Abstract: An erosion and corrosion resistant coating is formed of a plurality of alternating layers of metallic and ceramic materials. The two materials selected for the layers have complementary wear resistant characteristics, such that one is relatively ductile and the other is relatively brittle. The concentration of the two materials at the interface between adjacent layers is graded to improve the adhesion of the layers and to provide a more unified coating. Preferably radio-frequency sputtering is employed to deposit the coating, since it does not produce excessive heating which could negate any prior heat treatment of the substrate onto which the coating is deposited.