Abstract:
A method to limit surface zone recrystallization in a superalloy article includes limiting recrystallization in a surface zone of a superalloy article by treating the superalloy article in an oxygen-containing environment to introduce oxygen into the surface zone in an amount sufficient to pin any new grain boundaries in the surface zone.
Abstract:
A method for preparing an iridium tip with atomic sharpness. The method includes tapering an iridium wire to a needle shape and heating the iridium needle in an oxygen atmosphere. Also disclosed is an iridium needle having a pyramidal structure which terminates with a small number of atoms prepared by the methods.
Abstract:
An object of the present invention is to provide a gas turbine for power generation operated at a turbine nozzle inlet temperature ranging from 1200 to 1650null C., which is improved to obtain a high heat efficiency by making disk blades and nozzles arranged in first to final stages from optimum materials and optimally cooling these disk blades and nozzles, and a combined power generation system using the gas turbine. The present invention provides a combined power generation system including a highly efficient gas turbine operated at a turbine nozzle inlet combustion gas temperature ranging from 1200 to 1650null C., and a high pressure-intermediate pressure-low pressure integral type steam turbine operated at a steam inlet temperature of 530null C. or more, wherein the gas turbine is configured such that turbine blades, nozzles and disks are each cooled, and the blades and nozzles are each made from an Ni-based alloy having a single crystal or columnar crystal structure and disks are made from a martensite steel.
Abstract:
A method is disclosed for forming a biaxially textured buffer layer on a biaxially oriented metal substrate by using a sol-gel coating technique followed by pyrolyzing/annealing in a reducing atmosphere. This method is advantageous for providing substrates for depositing electronically active materials thereon.
Abstract:
In order to provide an austenitic single crystal stainless steel having preferable stress corrosion cracking resistance, strength, and irradiation induced embrittlement resistance so as to extend the life of a nuclear reactor core structure, which is used under a high radiation dose environment, a method is employed, which comprises the steps of homogeneously dispersing carbides into a parent phase of the austenitic single crystal stainless steel by a two step solution heat treatment, and subsequently effecting an ageing heat treatment after rapid cooling for precipitating fine carbides. Austenitic single crystal stainless steel having preferable stress corrosion cracking resistance, strength, and irradiation induced embrittlement resistance can be provided, and the life of nuclear reactor core structure, which is used under a high radiation dose environment, can be extended.
Abstract:
A superconducting article includes a biaxially-textured Ni substrate, and epitaxial buffer layers of Pd (optional), CeO.sub.2 and YSZ, and a top layer of in-plane aligned, c-axis oriented YBCO having a critical current density (J.sub.c) in the range of at least 100,000 A/cm.sup.2 at 77 K.
Abstract:
A biaxially textured alloy article includes a rolled and annealed biaxially textured base metal substrate characterized by an x-ray diffraction phi scan peak of no more than 20.degree. FWHM; and a biaxially textured layer of an alloy or another material on a surface thereof. The article further includes at least one of an electromagnetic device or an electro-optical device epitaxially joined to the alloy.