Abstract: A protective barrier coating system including a diffusion barrier coating and an oxidation barrier coating and method for use in protecting silicon-based ceramic turbine engine components. A complete barrier coating system includes a thermal barrier coating of stabilized zirconia and an environmental barrier coating of an alloyed tantalum oxide. The oxidation barrier coating includes a layer of metallic silicates formed on a substrate of silicon nitride or silicon carbide to be protected. The oxidation barrier coating can include silicates of scandium, ytterbia or yttrium. The oxidation barrier coating may also include an inner layer of Si2ON2 between the diffusion barrier and the metallic silicate layer. The oxidation barrier coating can be applied to the substrate by spraying, slurry dipping and sintering, by a sol-gel process followed by sintering, by plasma spray, or by electron beam-physical vapor deposition.

Abstract: Sintered silicon nitride products comprising predominantly ?-silicon nitride grains in combination with from about 0.1 to 30 mole % silicon carbide, and grain boundary secondary phases of scandium oxide and scandium disilicate. Such products have high fracture toughness, resistance to recession, and resistance to oxidation at temperatures of at least 1500° C. Methods for preparing sintered silicon nitride products are also disclosed.

Abstract: A component comprising a silicon-based substrate and a diffusion barrier coating disposed on the silicon-based substrate. The diffusion barrier coating comprises an isolation layer disposed directly on the silicon-based substrate and at least one oxygen barrier layer disposed on the isolation layer. The oxygen barrier layer prevents the diffusion of oxygen therethrough, and prevents excessive oxidation of the silicon-based substrate. The isolation layer(s) prevent contaminants and impurities from reacting with the oxygen barrier layer. An environmental barrier coating may be disposed on the diffusion barrier coating, and a thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a component having a diffusion barrier coating are also disclosed.

Abstract: A method and superalloy component for depositing a layer of material onto gas turbine engine components by atomic layer deposition. A superalloy component may have a ceramic thermal barrier coating on at least a portion of its surface, comprising a superalloy substrate and a bonding coat; and aluminum oxide (Al2O3) layer may be deposited on top of an yttria-stabilized zirconia layer and form a bonding coat by atomic layer deposition. The yttria-stabilized zirconia layer may have a plurality of micron sized gaps extending from the top surface of the ceramic coating towards the substrate and defining a plurality of columns of the yttria-stabilized zirconia layer. Also, atomic layer deposition may be used to lay an aluminum oxide (Al2O3) layer over a tantalum oxide (Ta2O5) layer on a silicon-based substrate.

Abstract: A component comprising a silicon-based substrate and a braze-based protective coating disposed on the silicon-based substrate. The braze-based coating comprises a brazed layer, wherein the brazed layer comprises at least one intermetallic compound. A scale layer may be formed on the brazed layer. An environmental barrier coating may be disposed directly on the brazed layer or directly on the scale layer. A thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a Si-based component having a braze-based protective coating are also disclosed.

Abstract: In one embodiment, move buses utilized in presently known VLIW processors are eliminated and replaced with a busing scheme which results in transfer of operands from each register file bank to any data path block while also reducing the total bus width and total power consumption associated with transport of operands from register file banks to data path blocks. According to this busing scheme, the speed of VLIW processor is also improved since the need for one clock cycle to move operands from one register file bank to another is overcome. In another embodiment, a scheduling restriction is used to eliminate the need for the presently required write back buses used by various data path blocks. In yet another embodiment, a scheduling restriction is imposed which results in a reduction of the number of ports, a reduction in the width of buses, and a reduction of power consumption.

Abstract: A protective coating for a component comprising a ceramic based substrate, and methods for protecting the component, the protective coating adapted for withstanding repeated thermal cycling. The substrate may comprise silicon nitride or silicon carbide, and the protective coating may comprise at least one tantalate of scandium, yttrium, or a rare earth element. The protective coating may further comprise one or more metal oxides. The coating protects the substrate from combustion gases in the high temperature turbine engine environment. The coating may be multi-layered and exhibits strong bonding to Si-based substrate materials and composites.

Abstract: A turbomachinery component includes a substrate having a surface, the surface being a material consisting essentially of at least one compound having the chemical formula Mn+1AXn, wherein M is at least one early transition metal selected from groups IIIB, IVB, VB, and VIB, A is at least one element selected from groups IIIA, IVA, VA, VIA, and VIIA, X is one or both of carbon and nitrogen, and n is an integer between 1 and 3. The component is made by forming a compact and sintered substrate with the material, or by coating a substrate with the material.

Abstract: Sintered silicon nitride products comprising predominantly ?-silicon nitride grains in combination with from about 0.1 to 30 mole % silicon carbide, and grain boundary secondary phases of scandium oxide and scandium disilicate. Such products have high fracture toughness, resistance to recession, and resistance to oxidation at temperatures of at least 1500° C. Methods for preparing sintered silicon nitride products are also disclosed.

Abstract: A turbomachinery component includes a substrate having a surface, the surface consisting essentially of at least one composite of at least one metal and at least one compound having the chemical formula Mn+1AXn, wherein M is at least one early transition metal selected from groups IIIB, IVB, VB, and VIB, A is at least one element selected from groups IIIA, IVA, VA, VIA, and VIIA, X is one or both of carbon and nitrogen, and n is an integer between 1 and 3. The component is made by compressing a powdered material to form a substrate that consists essentially of the composite and sintering the substrate, or by coating a substrate with the composite.

Abstract: A method and superalloy component for depositing a layer of material onto gas turbine engine components by atomic layer deposition. A superalloy component may have a ceramic thermal barrier coating on at least a portion of its surface, comprising a superalloy substrate and a bonding coat; and aluminum oxide (Al2O3) layer may be deposited on top of an yttria-stabilized zirconia layer and form a bonding coat by atomic layer deposition. The yttria-stabilized zirconia layer may have a plurality of micron sized gaps extending from the top surface of the ceramic coating towards the substrate and defining a plurality of columns of the yttria-stabilized zirconia layer. Also, atomic layer deposition may be used to lay an aluminum oxide (Al2O3) layer over a tantalum oxide (Ta2O5) layer on a silicon-based substrate.

Abstract: A protective barrier coating system including a diffusion barrier coating and an oxidation barrier coating and method for use in protecting silicon-based ceramic turbine engine components. A complete barrier coating system includes a thermal barrier coating of stabilized zirconia and an environmental barrier coating of an alloyed tantalum oxide. The oxidation barrier coating includes a layer of metallic silicates formed on a substrate of silicon nitride or silicon carbide to be protected. The oxidation barrier coating can include silicates of scandium, ytterbia or yttrium. The oxidation barrier coating may also include an inner layer of Si2ON2 between the diffusion barrier and the metallic silicate layer. The oxidation barrier coating can be applied to the substrate by spraying, slurry dipping and sintering, by a sol-gel process followed by sintering, by plasma spray, or by electron beam-physical vapor deposition.

Abstract: A component comprises a silicon-based substrate; and a protective coating for the substrate. The protective coating includes tantalum oxide (Ta2O5) and an additive for suppressing transformation from beta Ta2O5 to alpha Ta2O5.

Abstract: A component comprising a silicon-based substrate and a braze-based protective coating disposed on the silicon-based substrate. The braze-based coating comprises a brazed layer, wherein the brazed layer comprises at least one intermetallic compound. A scale layer may be formed on the brazed layer. An environmental barrier coating may be disposed directly on the brazed layer or directly on the scale layer. A thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a Si-based component having a braze-based protective coating are also disclosed.

Abstract: A component comprises a silicon-based substrate; and a protective coating for the substrate. The protective coating includes tantalum oxide (Ta2O5) and an additive for suppressing transformation from beta Ta2O5 to alpha Ta2O5.

Abstract: A component comprising a silicon-based substrate and a diffusion barrier coating disposed on the silicon-based substrate. The diffusion barrier coating comprises an isolation layer disposed directly on the silicon-based substrate and at least one oxygen barrier layer disposed on the isolation layer. The oxygen barrier layer prevents the diffusion of oxygen therethrough, and prevents excessive oxidation of the silicon-based substrate. The isolation layer(s) prevent contaminants and impurities from reacting with the oxygen barrier layer. An environmental barrier coating may be disposed on the diffusion barrier coating, and a thermal barrier coating may be disposed on the environmental barrier coating. Methods for making a component having a diffusion barrier coating are also disclosed.

Abstract: Sintered silicon nitride products comprising predominantly ?-silicon nitride grains in combination with from about 0.1 to 30 mole % silicon carbide, and grain boundary secondary phases of scandium oxide and scandium disilicate. Such products have high fracture toughness, resistance to recession, and resistance to oxidation at temperatures of at least 1500° C. Methods for preparing sintered silicon nitride products are also disclosed.

Abstract: An environmentally and thermally protected component comprising a silicon-based ceramic or composite substrate and an environmental and thermal barrier coating disposed on the substrate. The environmental and thermal barrier coating comprises at least about 50 mole % AlTaO4. The composition of the environmental and thermal barrier coating may be adapted to provide excellent CTE (coefficient of thermal expansion) match with a substrate, such as a SiC-based ceramic or composite. Coating compositions of the invention have a stable crystalline structure at a temperature up to at least about 1550° C. Methods for preparing an environmentally and thermally protected component are also disclosed.

Abstract: A component comprises a silicon-based substrate; and a protective coating for the substrate. The protective coating includes tantalum oxide (Ta2O5) and an additive for suppressing transformation from beta Ta2O5 to alpha Ta2O5.

Abstract: A turbomachine component includes a silicon nitride substrate and a protective coating on the substrate. The protective coating includes a porous silicon nitride matrix and a noble metal infiltrated in the porous silicon nitride matrix.