Date of Award

6-2008

Document Type

Thesis

Degree Name

Master of Science in Aeronautical Engineering

Department

Department of Aeronautics and Astronautics

First Advisor

Anthony N. Palazotto, PhD

Abstract

Thermal barrier coatings (TBCs) are currently used in turbine engine components to protect substrate material from being exposed to high temperatures and corrosion. These coatings also have the potential to reduce stress in critical engine parts which could increase the life cycle of these parts. The fact that these coatings are already qualified for use in turbine engines makes it worth investigating their damping properties. The problem with TBCs is that they are difficult to characterize as they display nonlinear properties. This research utilizes an experimental and finite element procedure to characterize these coatings. A scanning electron microscope (SEM) was also employed to observe the microstructure contribution to the damping properties. This program utilizes a testing method which employs a test setup that attempts to eliminate any external factors which may add any unwanted damping. The major contributions of this research are: a comparison of the material properties of two different thermal barrier coatings, magnesium aluminate spinel and yttria stabilized zirconia; the confirmation that sweep rate does not cause data recorded in the log decrement method to coincide with data recorded with the half-power bandwidth method; and SEM images that confirm the damping properties of plasma sprayed thermal barrier coatings are directly related to the crack structure of a coating on a microstructural level.

AFIT Designator

AFIT-GAE-ENY-08-J05

DTIC Accession Number

ADA483839

Download

Share

COinS