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 double-wall airfoil for applications such as the blades and vanes of gas turbine engines. The double-wall comprises an outer airfoil skin and an inner support wall that are metallurgically bonded to one another. The double-wall contains integral channels for passage of cooling air adjacent to the airfoil skin. Airfoil skin may be a metal alloy skin or a microlaminate structure, including microlaminate composite structures. Microlaminate composites typically have a lower density than that of the material used for the airfoil support wall, and a simplified internal geometry which promote weight reductions in the airfoils and increases in engine operating efficiency.

Abstract: An evaporation method is described for the deposition of various materials that comprise a plurality of elements, such as metal alloys, ceramics and certain inorganic-metallic compounds. The method involves the evaporation of a material comprising a plurality of elements through a molten pool of another material. The material which is to be evaporated is placed in a suitable evaporation means under the material which is to be used to form the molten pool. By applying heat sufficient to melt both materials, the material to be evaporated is transported through the molten pool of the other material. The materials are selected so that the material to be evaporated is preferentially evaporated with respect to the other material. This method produces a vapor stream and condensates that have compositions which closely resemble the compositions of the material from which they were deposited. Further, the condensate may be collected using the method of this invention at high rates on the order of 0.

Abstract: An article having a substrate is protected by a thermal barrier coating system. An interfacial layer contacts the upper surface of the substrate. The interfacial layer may comprise a bond coat only, or a bond coat and an overlay coat. The interfacial layer has on its upper surface a preselected, controllable pattern of three-dimensional features, such as grooves in a parallel array or in two angularly offset arrays. The features are formed by an ablation process using an ultraviolet laser such as an excimer laser. A ceramic thermal barrier coating is deposited over the pattern of features on the upper surface of the interfacial layer.

Abstract: Evaporated ceramic coatings are prepared by furnishing an ingot of a ceramic material, treating the ingot to reduce sources of gas within the ingot, and evaporating the ceramic material in the ingot by melting the surface of the ingot with an intense heat source. The evaporated ceramic is deposited upon a substrate as the ceramic coating. The reduced gas content of the ingot decreases the incidence of spitting and eruptions from the molten surface of the ingot, thereby improving the quality of the deposited coating, and facilitating increases in evaporation rates and coatings process production rates.

Abstract: Wear resistant cutting tools are comprised of cutting tools implanted with at least one element selected from the group consisting of, chlorine, fluorine, bromine, iodine, sulfur, indium, gallium and tin. The elements are implanted within the cutting tools in at least an effective amount to increase the wear resistance of the insert, up to an amount that does not substantially impair the hot hardness and toughness of the tool.In a method for lubricating the interface between a cutting tool and a workpiece in a lathe turning operation, at least one element selected from the group consisting of fluorine, bromine, iodine, sulfur, indium, gallium and tin are implanted in the tool. The elements are implanted so that the elements can lubricate the interface between the cutting edge and workpiece during turning without substantially impairing the hot hardness and toughness of the cutting tool.

Abstract: A layer of aluminum oxide or other insulative metal oxide is employed as an etch stop in the fabrication of very large scale integrated circuit devices. The use of such etch stops permits fabrication of unframed or borderless via openings and correspondingly permits greater metallization line pitch, smaller circuit features, and more reliable interlayer electrical contact. A method for insulative metal oxide deposition is also described.

Abstract: Nematic liquid crystal mixtures characterized by a homeotropic boundary condition are prepared by the addition of soluble monopolar compounds to either positive or negative dielectric anisotropic nematic materials. Between approximately 0.5 and 5 percent by weight of compounds such as certain carboxylic acids, aliphatic amines and aliphatic nitriles, for example, when dissolved in a nematic material produce spontaneous homeotropic boundary conditions therein.