摘要:
A turbine engine component is provided which has a substrate, a yttria-stabilized zirconia coating applied over the substrate, and a molten silicate resistant outer layer. The molten silicate resistant outer layer is formed from gadolinia or gadolinia-stabilized zirconia. A method for forming the coating system of the present invention is described.
摘要:
A turbine engine component is provided which has a substrate and a thermal barrier coating applied over the substrate. The thermal barrier coating comprises at least one layer of a first material selected from the group consisting of a zirconate, a hafnate, a titanate, and mixtures thereof, which first material has been mixed with, and contains, from about 25 to 99 wt % of at least one oxide. The at least one oxide comprises at least one oxide of a material selected from the group consisting of lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium, gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium, lutetium, scandium, indium, and yttrium. If desired, a metallic bond coat may be present between the substrate and the thermal barrier coating system. A method for forming the thermal barrier coating system of the present invention is described.
摘要:
A process of coating an article includes the steps of (1) applying a ceramic based compound to at least one surface of an article to form a layer of ceramic based compound; (2) applying at least one inert compound upon the ceramic based compound layer to form a protective layer, wherein the at least one inert compound is composed of a first inert compound having a cubic crystalline structure of formula (I) A3B2X3O12, or a second inert compound comprising a hexagonal crystalline structure of formula (II) A4B6X6O26, or a mixture of the first inert compound and the second inert compound; (3) optionally drying the coated article; (4) optionally repeating steps (2) and (3); and (5) heat treating the coated article.
摘要:
A spallation resistant metallic article comprising a metallic substrate, at least one ceramic thermal barrier coating comprising a zirconia base and at least one other element selected from the group consisting of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, Sc, In, Y, Mo and C, rare earth oxides, scandium, and indium, and a ceramic bond coat located on at least a portion of the substrate and between the metallic substrate and the at least one ceramic thermal barrier coating wherein the ceramic bond coat is composed of yttria stabilized zirconia (YSZ).
摘要:
A turbine component has a substrate formed from a ceramic material selected from the group consisting of a monolithic ceramic material and a composite ceramic material and a thermal barrier coating bonded to the substrate. In one embodiment, the ceramic material forming the substrate is selected from the group of silicon nitride and self-reinforced silicon nitride. In another embodiment, the ceramic material forming the substrate is selected from the group consisting of a silicon carbide-silicon carbide material and a carbon-carbon material. At least one bond coat layer may be interposed between the substrate and the thermal barrier coating.
摘要:
A method for creating a guardband that incorporates statistical models for test environment, system environment, tester-to-system offset and reliability into a model and then processes a final guardband by factoring manufacturing process variation and quality against yield loss.
摘要:
A ceramic material has particular utility as a thermal insulating or thermal barrier coating on metallic substrates. The ceramic material includes gadolinia and hafnia, preferably forming gadolinia-hafnia. This material exhibits chemical stability, thermal stability and thermal insulating properties superior to those of currently used thermal barrier ceramics, and also provides resistance to sintering and erosion comparable to currently used ceramics. A preferred material has between about 3-70 mol. % hafnia, balance hafnia.
摘要:
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.
摘要:
A method and system permit monitoring of a call center agent or similar service representative in servicing calls in a call center by logging sessions. The logged sessions may be selectively played back based on a number of scheduling criteria, including time interval, a scheduling rule, a number of calls, a monitoring length, a random indicator, call type information, agent performance level information, call traffic information, and others. The method and system plays back those portions of the logged sessions that meet the scheduling criteria.
摘要:
A method is taught for modifying the coefficient of thermal expansion of a molybdenum disilicide matrix material, so as to permit preparation of ceramic fiber reinforced matrices having improved high temperature strength, creep resistance, toughness, and resistance to matrix cracking during thermal cycling.