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Book Part A Numerical Approach To Simulating Oxidation in Thermal Barrier Coatings(Elsevier, 2020) Saeidi,F.; Gurses,E.; Aslan,O.Computational analysis and simulation of multi-physics phenomena taking place in coating systems is still a challenging task. Specifically, for ceramic coatings used as a system of protection for base materials against elevated temperatures, known as thermal barrier coating (TBC) systems, construction of continuum level models which can express coupled nonlinear phenomena has attracted great attention. Thermal stresses, oxidation, creep and numerous other mechanisms and phenomena makes it even harder to model and simulate the behavior of TBCs. In this article, a new numerical model which allows simulation of oxidation and thermally grown oxide (TGO) of bond-coat is presented. Phase field theory is used with finite strain formulation and implemented using user element subroutine (UEL) in ABAQUS software for finite element method. Results are compared with experimental data available for TGO in the literature. © 2020 Elsevier Inc. All rights reservedArticle Citation - WoS: 19Citation - Scopus: 19Modeling and Simulation of Coupled Phase Transformation and Stress Evolution in Thermal Barrier Coatings(Pergamon-elsevier Science Ltd, 2020) Sait, Ferit; Aslan, Özgür; Gurses, Ercan; Aslan, Ozgur; Sait, Ferit; Aslan, Özgür; Sait, Ferit; Mechanical Engineering; Aerospace Engineering; Mechanical Engineering; Aerospace EngineeringThe thermally grown oxide layer is known to be responsible for the failure of coating systems due to the generation of severely high stresses. In this work, oxidation induced stresses generated in thermal barrier coating (TBC) systems are investigated for high temperature isothermal oxidation. In that sense, a comprehensive model, where phase transformation is coupled with mechanics is developed for the life-time estimation of TBC systems and a modified version of the Allen-Cahn type phase field approach is adopted in order to model the generation of thermally grown oxide (TGO) in finite strain constitutive framework. The top-coat material behavior is modeled using a rate-dependent Gurson type plasticity for porous materials which also accounts for creep. The results for the isothermal phase transformation analysis and the model validation using experimental results are demonstrated. The capability of the model in predicting the local stresses which is the main variable in the analysis of possible delaminations and accurate lifetime estimation of TBC systems is shown.
