General Electric Company

Transash

Daniel P Ivkovich, Jr

Andrew Jay Skoog

Jane Ann Murphy

Thomas Walter Rentz

John W Gerbus

A method of forming a multilayer ceramic coating system on a substrate that requires thermal protection from a hostile thermal environment. The method generally entails forming at least one tape that contains ceramic particles dispersed in an organic constituent, such as a binder and/or plasticizer. If a single tape is used, the tape is formed of multiple layers of different compositions and applied as a unit to the substrate, thereby forming at least an innermost layer and an outermost layer on the substrate. If multiple tapes are used, a first tape is applied to the substrate to form the innermost layer, and a second tape is applied to form the outermost layer. The tape/tapes are then sintered to form innermost and outermost ceramic layers, respectively, on the substrate. The tape/tapes are formed and processed such that the innermost ceramic layer has submicron voids to provide a desired level of porosity, while the outermost ceramic layer is thinner, smoother and less porous than the innermost ceramic layer.

Method of forming a multilayer ceramic coating

Gas turbine engine component having a thermal-insulating multilayer

A method for making aggregate includes the following steps: (a) preparing a wet mixture by mixing water with a combination of ingredients in a mixer, the combination of ingredients including by weight about, 68% to 95% fly-ash and 2% to 10% lime; (b) dropping the wet mixture into at least one pile on a base surface; (c) allowing the wet mixture in the pile to substantially completely hydrolyze into a hard product; and (d) crushing the product to form the aggregate. Preferably, step (b) further includes forming an arcuate stack having multiple overlapping conical piles of the dropped wet mixture such that the stack extends a circular distance over the surface. The wet mixture may be transported from the mixer to a height above the surface and dropped to the surface by a radial stacker. The combination of ingredients, preferably, further includes by weight 0.5% to 12% alkali hydroxide and, more particularly, sodium hydroxide.

Method for producing aggregate

The present invention provides a method and mixture for use in forming strong light-weight aggregate and includes by weight about; 68% to 95% fly-ash, 2% to 10% hydrated lime, and 3% to 12% alkali hydroxide such as Sodium Hydroxide. While many types of fly-ash may be used, Type F or Type C fly-ash are preferred. The admix is mixed with water to form a slurry including water in a range of 10% to 25% by weight of the dry mixture and the slurry is then compacted. The compacted slurry is then cured such as by using a rotary kiln or by in situ open air curing. The cured slurry is then allowed to hydrolyzed to form a hard material which then may be crushed and optionally screened to form an aggregate having a particular size or range of sizes.

Growing community of inventors

Fairfield, OH, United States of America

Daniel P Ivkovich, Jr