Pindera, J. Aboudi and S.M. Arnold

Herein, the two-dimensional version of the higher-order theory [6-7], briefly outlined below, is employed to investigate the effect of different levels of microstructural refinement on the internal stress field in a functionally graded TBC subjected to cyclic thermal loading in the presence of creep of the ceramic phase. 

Given the applied thermal loading, an approximate solution for the temperature and displacement fields is constructed by first approximating the temperature distribution in each subcell of a generic cell using a quadratic expansion in the local coordinates x.  

The material properties of the individual constituents are given in Table 1. Due to the low conductivity of zirconia, and the significant temperature drop in the pure zirconia layer, 

Comparing the stress distributions in the coarse and the fine TBC microstructures generated with the higher-order analysis, we observe virtually no difference in the pure ceramic region. In the functionally graded regions, differences are expected due to differences in the microstructural scales. However, one common feature exhibited by the stress distributions in the two mierostructures is the common envelope within which the stress oscillations in the 

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