Combining digital image processing with finite element mesh generation, finite element models based on actual microstructures of plasma sprayed zirconia coatings were built. By employing finite element method in conjunction with Fourier’s equation, the apparent thermal conductivity of zirconia coatings affected by defects, including pores and cracks were calculated. For comparison, the coating’s thermal conductivity was measured by the laser pulse method. The difference between values of the finite element method and experimental results are told to analyze effects of defects and splat interfaces on the thermal conductivity. The results show that splat interfaces are as equally important as defects in defining the thermal conductivity of plasma sprayed coatings in the spray direction.
SHEN Wei, FAN Qun-Bo, WANG Fu-Chi, MA Zhuang, YANG Xue-Wen
. Finite Element Study of Influence Factors on Thermal Conductivity of Plasma Sprayed Zirconia Coatings Based on Digital Image Processing[J]. Journal of Inorganic Materials, 2010
, 25(11)
: 1217
-1220
.
DOI: 10.3724/SP.J.1077.2010.01217
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