| Modeling Thermal Conductivity of Thermal Spray Coatings: Comparing Predictions to Experiments | ||
| Mr. Yang Tan1, Jon P. Longtin1 and Prof. Sanjay Sampath2, 1Mechanical Engineering, Stony Brook University, Department of Mechanical Engineering, Stony Brook University, Stony Brook, NY 11794, 2Center for Thermal Spray Research, Stony Brook Univerisity, Department of Materials Science and Engineering, Stony Brook Univerisity, Stony Brook, NY 11794-2275
Thermal conductivity and electrical resistivity play a critical role in the thermal and electrical transport of thermal sprayed coatings. In this paper, a combined image analysis and finite element method approach is developed to estimate thermal and electrical resistivity from high-resolution scanning electron microscopy images of the coating microstructure. Images are analyzed with a collection of image processing algorithms to reveal the microscopic detailed coating morphology. The processed digital image is used to generate a two-dimensional finite element meshing in which pores, cracks and the bulk coating material are identified. The effective thermal conductivity or electrical resistivity is then simulated using a commercial finite element code. Results are presented for three coating material systems processed through various thermal spray methods: yttria stabilized zirconia (YSZ), Molybdenum and NiAl, and results are found to be in good agreement with experimental values from the laser flash method. Coatings are also annealed and the analysis procedure repeated to determine if the technique can accurately assess changes in coating morphology. | ||