Abstract: An article is described, which includes a metal-based substrate, such as a superalloy; a dense, primary bond layer; and a spongy secondary bond layer. A thermal barrier coating is applied over the secondary bond layer. The spongy layer has a microstructure which includes an open network of interconnected pores. A process is also described. It includes the step of applying a spongy, metallic bond layer over the substrate, followed by the application of a thermal barrier coating. A dense, primary bond layer may optionally be applied before the application of the spongy layer.

Abstract: An implantable rotary blood pump including a rotor mounted for rotation within a pump housing. The rotor has a shaft portion and an impeller carried by the shaft portion. A rotor motor is provided, with a motor including a plurality of permanent magnets carried by the impeller and motor stators on opposite sides of the impeller. Structural members are provided between the impeller and stators to provide structural support and hermetical sealing. The structural members comprise biocompatible, corrosion resistant, electrically non-conducting ceramic material, which alleviate eddy current losses.

Abstract: A coating system (20) for articles used in hostile thermal environments, such as turbine, combustor and augmentor components (10) of a gas turbine engine. The coating system (20) of this invention employs a NiAl-based intermetallic coating (24) containing 30 to 60 atomic percent aluminum so as to be predominantly of the .beta.-NiAl phase, but also contains alloying additions intended to increase the creep strength of the coating (24), and optionally contains alloying additions to getter impurities, increase fracture resistance, and promote oxidation resistance. For this purpose, the coating (24) preferably includes additions of chromium, titanium, tantalum, silicon, hafnium and/or gallium, and optionally contains additions of calcium, zirconium, yttrium, and/or iron.

Abstract: On a turbine blade a protective corrosion resistant surface layer consisting of a MCrAlY alloy is generated by melting the surface of the turbine blade with the MCrAlY alloy uniformly distributed over the surface of the turbine blade by a pulsed electron beam to a depth of 5-50 .mu.m whereby a smooth surface is generated.

Abstract: The invention relates to an article of manufacture comprising: a substrate composed of a superalloy containing chromium and a base element selected from the group consisting of iron, cobalt, and nickel; and an enrichment layer containing chromium and placed on the substrate. Therein, the enrichment layer comprises a continuous matrix composed of a gamma-phase solid solution of chromium in the base element. The invention also relates to the manufacture of such an article. The article may in particular be a gas turbine component.

Abstract: A compliant sleeve for attaching a ceramic member to a metal member is comprised of a superalloy substrate having a metal contacting side and a ceramic contacting side. The ceramic contacting side is plated with a layer of nickel followed by a layer of platinum. The substrate is then oxidized to form nickel oxide scale on the ceramic contacting side and a cobalt oxide scale on the metal contacting side. A lubricious coating of boron nitride is then applied over the metal contacting side, and a shear-stress limiting gold coating is applied over the ceramic contacting side.

Abstract: High temperature oxidation resistance of an aluminide diffusion overcoated MCrAlY coating system is substantially improved by CVD over-aluminizing the MCrAlY type overlay coating under CVD conditions that result in reduced concentrations of such tramp impurities as S and P in the aluminized MCrAlY overlay coating region of the coating system. The CVD aluminizing conditions yield an outwardly grown aluminide over-coat on the underlying MCrAlY type coating.

Abstract: An airfoil having extended life due to reduction in stresses. The stresses are reduced by extending the thermal barrier coating below the radius between the outer band perimeter and the inner flow path surfaces and tapering the coating thickness. This additional tapered thermal barrier coating reduces the temperature gradient across a region already having high mechanical stresses resulting from geometric considerations thereby lowering thermally-induced stresses so that low cycle fatigue life is improved.

Abstract: An article of manufacture includes a substrate and an anchoring layer disposed on a surface of the substrate. The substrate is capable of developing a first oxide on the surface which is tightly bonded thereto and includes a first metallic element. Alternatively, the surface is formed of the first oxide. The anchoring layer is formed with a ternary oxide of the first metallic element, a second metallic element and oxygen. A second oxide layer, which contains an oxide of the second metallic element, is disposed on the anchoring layer. The anchoring layer is formed on the substrate in a series of process steps, which include: establishing an atmosphere containing oxygen around the article; evaporating a compound of the first metallic element and a compound of the second metallic element into the atmosphere and forming a ternary gas phase containing the first metallic element, the second metallic element and the oxygen; and precipitating the ternary gas phase on the article.

Abstract: A new family of ceramic materials is identified having particular utility as thermal insulating or thermal barrier coatings on metallic substrates. The ceramic materials have a pyrochlore structure and are typified by the composition A.sub.2 B.sub.2 O.sub.7 where A and B are various ions and O is oxygen. A may have a positive charge of 3.sup.+ or 2.sup.+ and B may have a positive charge of 4.sup.+ or 5.sup.30. These materials are characterized by having chemical stability, thermal stability and thermal insulating properties superior to those of currently used thermal barrier ceramics. An example pyrochlore material is lanthanum zirconate.

Abstract: A metallic article includes a bond coating and a ceramic thermal barrier coating on the bond coating. The ceramic thermal barrier coating includes a plurality of columnar grains extending substantially perpendicularly to the surface of the metallic article. Each columnar gain has a plurality of first layers, a plurality of second layers and a plurality of third layers. The first layers have a different structure from the second layers and the third layers. The second layers have a different structure from the third layers. The first layers have the same composition as the third layers. The second layers have a greater proportion of voids than the first layers and the third layers. The voids reduce the thermal conductivity of the thermal barrier coating. The second layers may also have a different composition from the first layers and the third layers to reduce the thermal conductivity.

Abstract: The present invention generally describes multilayer thermal barrier coating systems and methods of making the multilayer thermal barrier coating systems. The thermal barrier coating systems comprise a first ceramic layer, a second ceramic layer, a thermally grown oxide layer, a metallic bond coating layer and a substrate. The thermal barrier coating systems have improved high temperature thermal and chemical stability for use in gas turbine applications.

Abstract: This invention discloses new and improved multi-layer coatings for gas turbine engine parts that are exposed to elevated temperatures, such as blades and vanes in the high pressure compressor and turbine of multi-stage aircraft engines, by applying a diamond film over columnar thermal barrier coatings such as yttria-stabilized zirconia, improving the erosion resistance of the thermal barrier coating.

Abstract: A monitor for detecting overheating of a critical component in a combustion turbine is provided. The monitor, when used in conjunction with a closed-loop cooling system, comprises a coating comprising an indicator material having an activation temperature. The coating is situated on the internal cooling passages of the critical component. The monitor further comprises a sensor connected to an outlet conduit of the cooling system for determining the amount of degradation of indicator material by monitoring the cooling fluid flowing through the outlet conduit. Embodiments further comprising "sniffer" tubes for use with open-loop air cooling systems also are provided.

Abstract: A vibration damped turbo-machine blade includes a shot peened metallic substrate which provides a shape for the blade. Carried on the metallic substrate and bonded to an outer surface of this substrate is a singular ceramic coating of a damping material. The substrate may be made of forged titanium, and the coating may be made of a ceramic material including cobalt at a weight percentage of from about 13% to about 21%, with the balance of the ceramic material being substantially all tungsten carbide.

Abstract: An overcoat is applied over thermal barrier coatings such as YSZ or other columnar grain ceramic. The exposed surface of the TBC is prepared to ensure that it is clean and has a proper roughness. The surface is then heated and an overcoat material such as a solid solution of chromia and alumina is deposited on the exposed surface, for example by plasma spraying to form a continuous overcoat on the TBC. The overcoat is preferably corrosion and erosion resistant, and inhibits the migration of oxygen to the underlying TBC and alumina layer.

Abstract: Layered ceramic coatings in which some layers contain porosity as described as are methods for producing such coatings. The different layers have different compositions and/or are applied under different conditions. As applied, some of the layers have a Zone I structure and some have a Zone II/III type structure (as defined by Movchan). Heat treatment can be used to increase the porosity in the Zone I structure layers.

Abstract: The invention provides an improved thermal barrier coating system for a hot section component. The thermal barrier coating has a metallic bond coat and a ceramic top coat made of two constituents. The top coat is formed so that there is provided a graded interface between the monolithic layers of the two top coat constituents. This allows an increase in overall thickness of the thermal barrier coating which provides a higher thermal insulation for the component being protected.

Abstract: A ceramic-coated blade of a gas turbine and a method of producing the same, in which the thickening of an Al.sub.2 O.sub.3 layer at the interface between a ceramic layer and a primary layer is sufficiently prevented for a long period of time, thereby positively suppressing the separation of the ceramic layer. Using powder of MCrAlY alloy (Co-32% Ni-21% Cr-8% Al-0.5% Y), a primary layer (alloy coating layer) is formed on a surface of a substrate made of a heat-resistant Ni base alloy (Rene'-80). Further, a heat-resistant ceramic layer, comprising a mixture of ion-conductive ZrO.sub.2 -8 wt. % Y.sub.2 O.sub.3 ceramic and insulative ceramic (e.g. Al.sub.2 O.sub.3), is formed on the alloy coating layer. This mixture has a columnar structure in which columnar crystals are grown by a gas phase in a direction of a thickness of the coating, or a porous structure in which flattened particles brought about from molten particles caused to fly at high velocity are laminated.

Abstract: A turbine blade which can be subjected to a hot gas flow includes a substrate, at least one interior space and a plurality of bores leading from the interior space out of the substrate. The substrate is at least partly covered by a heat-insulating-layer system at a suction side and/or a pressure side. At least one of the bores is closed by the heat-insulating-layer system and at least one further bore is open for developing film cooling.

Abstract: A non-metallic pump for pumping molten metal includes a motor, a shaft having one end connected to the motor and an impeller connected to the other end of the shaft. A base has a chamber in which the impeller is rotatable. Structure is used to removably insert the base into a bath of molten metal. The impeller includes stirrer openings which are configured and arranged to enable the impeller to cause solid matter in the molten metal to move toward an upper surface of the bath.

Abstract: A method for identifying ceramics suitable for use as thermal barrier coatings is presented, based on parameters associated with thermal conductivity, oxygen diffusivity, thermal expansion coefficient, maximum temperature capability, hardness, elastic modulus, density, and chemical reactivity. A ceramic thermal barrier coating and method of manufacture is further presented, the ceramic comprising yttrium aluminum garnet (Y.sub.3 Al.sub.5 O.sub.12, or YAG)-based ceramics. Such ceramics are based on yttrium aluminum garnet or other ceramics with the garnet structure and alloys thereof. The ceramics in accordance with the present invention have low thermal conductivity, and are more potentially durable than prior art zirconia based ceramics.

Abstract: Stabilized zirconia containing sintered particles of alumina and zirconia tetragonal phase at temperatures below about 1150.degree. C. is prepared by mixing alumina particles of less than 30 nanometers with zirconia particles of less than 30 nanometers in presence of a liquid to form a suspension, drying the suspension at a temperature up to about 600.degree. C. to remove the liquid and products thereof to form a dried suspension composed of agglomerated alumina and zirconia particles, sintering the dried suspension to fuse the particles, and cooling the sintered dried suspension to an ambient temperature to produce free-standing bodies or coatings on substrates.

Abstract: 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).

Abstract: A granular composition is applied to tips of rotor blades utilized in a gas turbine engine wherein the blade tips rub against an abradable ceramic layer. Individual grains each have a core of silicon carbide and a layer of aluminum nitride on the core. A layer of a cladding metal may be bonded to the aluminum nitride. The composition also may include particles of cubic boron nitride and/or particles of metal alloy blended with the grains of silicon carbide.

Abstract: A protective coating for protecting a component from corrosion and oxidation at a high temperature and from excessive thermal stress, has a heat insulation layer including a ceramic material and an adhesion-promoting layer including a rhenium containing metal alloy. The metal alloy belongs to the alloys covered by the general term MCrAlY, where M represents cobalt and/or nickel and Y represents yttrium and/or at least one equivalent metal from the group including scandium and the rare earth elements. The protective coating is distinguished by high oxidation resistance and corrosion resistance of the alloy, by outstanding thermal fatigue properties and an effective and permanent bond between the alloy and the ceramic heat insulation layer. As a result of the heat insulation, the temperature at the outer surface of the protective coating can be considerably higher than with purely metallic protective coatings, without an increased thermal load being exerted on the component.

Abstract: A nickel-based or cobalt-based superalloy substrate is covered with a protective system which is resistant to thermal, corrosive and erosive attack. An anchoring layer is disposed on the substrate. The anchoring layer is formed as an oxide compound, in particular alumina, doped with nitrogen. A ceramic coating is disposed on the anchoring layer. The modification of the anchoring layer prevents the transmission of diffusing elements through the anchoring layer to the thermal barrier layer.

Abstract: A thermal insulating ceramic layer for use in a thermal barrier coating system on a component designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The ceramic layer is formed of zirconia stabilized by yttria and characterized by a columnar grain structure in which a monoclinic phase is present. To attain the monoclinic phase, the ceramic layer contains less than six weight percent yttria, with about two to five weight percent yttria being preferred. The ceramic layer is preferably part of a thermal barrier coating system that includes a substrate and a bond coat adhering the ceramic layer to the substrate. To obtain the desired columnar grain structure, the ceramic layer is deposited by a PVD technique, preferably EBPVD.

Abstract: A thermal barrier coating and a method for forming the coating on an article designed for use in a hostile thermal environment, such as turbine, combustor and augmentor components of a gas turbine engine. The method is particularly directed to increasing the spallation resistance of a thermal barrier coating system that includes a thermal insulating ceramic layer. The coating system of this invention generally includes a nickel aluminide alloy on which an aluminum oxide layer is formed, over which a ceramic layer is deposited so as to overlie and contact the aluminum oxide layer. The coating system does not include a bond coat, such as a diffusion aluminide or MCrAlY coating known in the prior art. The nickel aluminide alloy may be a binary NiAl alloy consisting essentially of nickel and aluminum in stoichiometric amounts, or may contain one or more oxygen-active elements.

Abstract: A device is disclosed for forwarding a medium in the form of a gas, liquid, or loose particles. The medium can contain additives and/or contaminants in an aggregate state other than that of the medium itself. The device's major components are form-fit and force-fit together and comprise at least one supporting component along with blade-like components fastened to it. The supporting component is, or the supporting components are, made of a fiber-filled composite. The device is in particular an impeller for a pump, turbine, or similar mechanism. It is characterized in that the supporting component is, or the supporting components are, made of a lattice of essentially continuous fibers of carbon and/or ceramic and of a matrix that contains carbon and in that the fibers are sheathed with silicon carbide resulting from the infiltration of liquid silicon and from its reaction essentially with the carbon in the matrix.

Abstract: A ceramic-metal composite assembly includes an intermediate member made of a material having a thermal expansion efficiency between those of the materials forming a ceramic member and a metallic shaft member. The intermediate member is metallurgically joined to the ceramic member whilst being mechanically joined to the metallic member to constitute a single unit.

Abstract: 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.

Abstract: A thermal barrier coating member to be used for such as a member for a gas turbine comprising a metallic member comprising a super alloy mainly composed of at least one of Ni, Co and Fe, an intermediate layer composed of a MCrAlY alloy (M denotes at least one of Ni, Co and Fe) covering this metallic substrate, and a ceramic layer mainly composed of stabilized zirconia formed on the intermediate layer. A ceramic material having a higher melting point than zirconia is compounded in the ceramic layer as a member for suppressing a reaction sintering of the ceramic layer.

Abstract: A multilayered ceramic topcoat of a thermal barrier coating system is useful for high temperature corrosive applications such as hot section components in gas turbine engines. The ceramic topcoat includes at least two layers, each having generally columnar grain microstructures with different grain orientation directions. A preferred method of producing the multilayered ceramic topcoat includes positioning a superalloy substrate at a first angled orientation relative to a ceramic vapor cloud in an electron beam physical vapor deposition apparatus for a time sufficient to grow a first ceramic layer. The substrate is then reoriented to a second, different angled orientation for a time sufficient to grow a second ceramic layer. The ceramic layers exhibit columnar microstructures having respective grain orientation directions which are related to the first and second substrate orientations.

Abstract: A improved thermal barrier coating and method for producing and applying such is disclosed herein. The thermal barrier coating includes a high temperature substrate, a first bond coat layer applied to the substrate of MCrAlX, and a second bond coat layer of MCrAlX with particles of a particulate dispersed throughout the MCrAlX and the preferred particulate is Al.sub.2 O.sub.3. The particles of the particulate dispersed throughout the second bond coat layer preferably have a diameter of less then the height of the peaks of the second bond coat layer, or a diameter of less than 5 .mu.m. The method of producing the second bond coat layer may either include the steps of mechanical alloying of particles throughout the second bond coat layer, attrition milling the particles of the particulate throughout the second bond coat layer, or using electrophoresis to disperse the particles throughout the second bond coat layer.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: A metal or ceramic matrix composite part and corresponding method are provided exhibiting desired heat transfer characteristics. The part has a metal or ceramic matrix composite substrate and a multilayer dielectric coating. The coating has high reflectivity at wave lengths corresponding to radiation wavelengths of various combustion gases and has low reflectance at radiation wavelengths corresponding to the substrate. The multilayer coating allows the heat generated external of the part at wavelengths corresponding to combustion gases to be reflected from the part while permitting radiation wavelengths associated with the substrate to pass through the coating. The parts are useful for use in combustive gas atmospheres.

Abstract: A single-crystal article having a thermal barrier coating on a surface thereof, and a method for processing the article so as to promote the life of the coating. As a result of its single-crystal microstructure, the article is characterized by having been unidirectionally solidified along a primary crystallographic direction, and secondary crystallographic directions that are normal to the primary crystallographic direction. Improved spallation resistance of the coating is achieved by selectively orienting the secondary crystallographic direction with respect to a direction normal to a life-limiting surface region of the thermal barrier coating.

Abstract: A ceramic coated heat-resistant element comprises a heat resisting alloy base mainly composed of Ni and/or Co and a heat-resistant coating layer provided on the surface of the base and is characterized in that said heat-resistant coating layer comprises a metal layer of an alloy superior to the base in high-temperature corrosion and oxidation resistance and provided on the base, an Al.sub.2 O.sub.3 ceramic thin film layer provided on the metal layer, a ZrO.sub.2 ceramic coating layer having dense texture provided on the Al.sub.2 O.sub.3 ceramic thin film layer and a ZrO.sub.2 ceramic coating layer having columnar texture provided on the ZrO.sub.2 ceramic coating layer having dense texture cracks are present only in the ZrO.sub.2 ceramic coating layer having columnar texture in the direction of thickness along the boundary of the columns. A mixed layer composed of a metal superior to the base in high-temperature corrosion and oxidation resistance and a ZrO.sub.

Abstract: In a thermally loaded blade for a turbomachine, the front edge of such a blade is made from a ceramic material for providing better protection. The front edge has a shell-shaped form which covers at least one part of the head stage against which flow occurs. The connection between front edge and head stage is produced on the one side by a coupling-forming indentation and on the other side by an elastic element. The elastic element produces a retaining action at the location where it is placed and a frictional connection, having an effect on the indentation, on the other side of the blade. Cooling air bores in the head stage provide for a cooling effect on the ceramic front edge.

Abstract: Zinc oxide stabilized zirconia containing zirconia in cubic phase is prepd by evaporating zirconia and zinc oxide and depositing zirconia and zinc oxide on an atomic scale on a substrate. The stabilized zirconia resists corrosion at high temperatures above 1000.degree. C., can be used as a part of a barrier coating, is transparent to visible light, and is electrically conducting.

Abstract: An impeller for a molten metal pump having a cylindrical body comprised of a refractory material. The cylindrical body includes generally coplanar top and bottom surfaces. A central bore is provided in the top surface to provide a point for mating with a shaft. A plurality of circumferentially spaced passages extend from the top surface to a side wall of the impeller, each of the passages being separate and preferably having an inlet opening which is equal to or less than the corresponding outlet opening in size.

Abstract: A ceramic blade for a hybrid type gas turbine blade has a dovetail portion, a platform portion formed on the dovetail portion and blade portions formed on the platform portion. The number of the blade portions formed on one platform portion is two or more. The upper surface of the platform portion is shaped into an arc-like form, and the dovetail portion is linearly formed in a tangential direction to a turbine rotation direction. By the utilization of this blade, the hybrid type gas turbine blade can inhibit the leakage of a gas and can be easily manufactured and is excellent in durability.

Abstract: A thermal barrier protected nickel based or cobalt based superalloy component for use in a gas turbine engine includes a thermal barrier coating system having a multi-layered structure. The first bondcoat layer of the thermal barrier coating system comprises a chemical vapor deposited, platinum modified diffusion aluminide layer on the superalloy component (substrate). The diffusion aluminide layer includes an inner diffusion zone proximate the substrate and an outer layer region comprising a platinum modified (platinum-bearing) intermediate phase of aluminum and at least one of nickel and cobalt depending on the superalloy composition. The intermediate phase is a non-ordered solid solution having a range of compositions and is free of other phase constituents.

Abstract: The performance of many macroscopic structures (those whose dimensions are on the order of centimeters, meters, or even larger) can be greatly improved by covering their surfaces with microstuctures. There are several applications in which "large," microstructure-covered sheets are useful. For example, dissimilar sheets of material that otherwise would not bond well to one another (such as a polymer and a metal) can be more strongly bonded with microstructures extending from one of the sheets and embedded into the other sheet. Such products make valuable laminate composites. As another example, the rate of heat transfer between an object and the surrounding medium can be dramatically changed (up or down) by covering the surface of the object with high aspect ratio microstructures, without significantly changing the component's size or weight.

Abstract: The invention relates to a titanium article of manufacture having an oxidation resistant surface and a process for producing such article wherein said titanium has an aluminized surface layer formed on it by the vapor deposition of aluminum on the titanium followed by oxidizing the surface layer.

Abstract: The surface of an aluminide is treated to make it less chemically reactive. In particular, this treatment inhibits oxidation of the aluminide at high temperatures. According to the invention, one coats the aluminide with a solution that containing phosphoric or phosphorous acid, and then one heats the aluminide, so as to calcine the coating. The phosphoric or phosphorous acid reacts with the aluminide to form a surface that resists oxidation. One can use this process to coat the blades of a gas turbine, or to coat other aluminide structures intended for use in high-temperature environments.

Abstract: The present invention provides ceramic coated heat-resistant elements which suffer no damages even under high heat load conditions and can afford a thermal barrier effect stably for a long period of time and can be used, for example, as buckets and stationary blades of turbines. A method for making the elements is also provided. The ceramic coated heat-resistant element comprises a heat resisting alloy base mainly composed of Ni and/or Co and a heat-resistant coating layer provided on the surface of the base and is characterized in that said heat-resistant coating layer comprises a metal layer of an alloy superior to the base in high-temperature corrosion and oxidation resistance and provided on the base, an Al.sub.2 O.sub.3 ceramic thin film layer provided on the metal layer, a ZrO.sub.2 ceramic coating layer having dense texture provided on the Al.sub.2 O.sub.3 ceramic thin film layer and a ZrO.sub.2 ceramic coating layer having columnar texture provided on the ZrO.sub.

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: In a non-metallic pump for pumping molten metal including a shaft, a motor at one end of the shaft, an impeller at the other end of the shaft, and a base having a chamber in which the impeller is rotatable, the improvement being a dynamically balanced impeller comprising a cylindrical center hub and five vanes extending outwardly from the hub, wherein the vanes are equally spaced around the periphery of the hub.