Peter Minor, PhD 2013
Advisor: Paul Wright
Ongoing Research into the Impact Durability of Thermal Barrier Coatings
Thermal barrier coatings are a widely used material system for prolonging the lifetime of critical structures subject to very high-temperature environments. One significant application of these coatings is gas turbine blades, which operate in excess of 1000 C. However, the ceramic layers of thermal barrier coatings have low fracture toughness and are vulnerable to foreign particle impact damage. An empirical study of these impacts would be extremely difficult due to the high temperature environment. Therefore, the purpose of my research is to develop models that investigate the nature of these impacts and the resulting effect on the coating microstructure. To accurately capture the complex failure mechanisms inherent to high-velocity impacts on ceramics, the thermal barrier coating microstructure will be represented using a large-scale particle dynamic simulation. Once a better understanding of the damage mechanisms can established, I hope to use the lessons learned to identify methods in which to improve the durability of thermal barrier coatings.
Figure 1: Gas turbine blade showing significant damage to the thermal barrier coating due to foreign object impact
Figure 2: Diagram showing the multiple modes of failure due to impact stresses