Effects of Layer Thickness and Edge Conditions to Thermoelastic Characteristics on Thermal Barrier Coatings

Jaegwi Go, Je-Hyun Lee

Department of Mathematics, Changwon National University, Changwon, South Korea.
School of Nano and Advanced Materials Engineering, Changwon National University, Changwon, South Korea.

DOI: 10.4236/am.2014.516233                

Abstract

The thermoelastic behaviors of such as temperature distribution, displacements, and stresses in thermal barrier coatings (TBC) are seriously influenced by top coat thickness and edge conditions. The top coat of TBC specimens prepared with TriplexPro?-200 system was controlled by changing the processing parameter and feedstock, showing the various thicknesses and microstructures. A couple of governing partial differential equations were derived based on the thermoelastic theory. Since the governing equations were too involved to solve analytically, a finite volume method was developed to obtain approximations. The thermoelastic behaviors of TBC specimens with the various thicknesses and microstructures were estimated through mathematical approaches with different edge conditions. The results demonstrated that the microstructure and thickness of the top coat, and the edge condition in theoretical analysis were crucial factors to be considered in controlling the thermoelastic characteristics of plasma-sprayed TBCs.

Keywords

Thermal Barrier Coatings, Air Plasma Spray, Layer Thickness, Thermoelastic Characteristics, Finite Volume Method

Conflicts of Interest

The authors declare no conflicts of interest.

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