Molten Particulate Impact on Tailored Thermal Barrier Coatings for Gas Turbine Engine

Abstract

Commercial/military fixed-wing aircraft and rotorcraft engines often have to operate in significantly degraded environments consisting of sand, dust, ash, and other particulates. Marine gas turbine engines are subjected to salt spray, while the coal-burning industrial power generation turbines are subjected to fly ash. The presence of solid particles in the working fluid medium has an adverse effect on the durability of these engines as well as performance. Typical turbine blade damages include blade coating wear, sand glazing, calcia–magnesia–alumina–silicate (CMAS) attack, oxidation, and plugged cooling holes, all of which can cause rapid performance deterioration including loss of aircraft. This research represents the complex thermochemomechanical fluid structure interaction problem of semimolten particulate impingement and infiltration onto ceramic thermal barrier coatings (TBCs) into its canonical forms. The objective of this research work is to understand the underpinning interface science of interspersed graded ceramic/metal and ceramic/ceramic composites at the grain structure level for robust coatings and bulk material components for vehicle propulsion systems. This research enhances our understanding of the fundamental relationship between interface properties and the thermomechanical behavior in dissimilar materials for materials by design systems, and creates the ability to develop and fabricate materials with targeted macroscale properties as a function of their interfacial behavior. This project creates a framework to enable the engineered design of solid–solid and liquid–solid interfaces in dissimilar functionalized materials to establish a paradigm shift toward science from the traditional empiricism in engineering TBCs and high temperature highly loaded bulk materials. An integrated approach of modeling and simulation, characterization, fabrication, and validation to solve the fundamental questions of interface mechanisms which affect the properties of novel materials will be validated to guide component material solutions to visionary 2040+ military vehicle propulsion systems.