B.D. Choules, K. Kokini and T.A. Taylor, "Thermal Fracture of Thermal Barrier Coatings in a High Heat Flux Environment", Surface and Coatings Technology, Vol. 106, pp. 23-29, 1998.

K. Kokini and M. Case, "Initiation of Surface and Interface Edge Cracks in Functionally Graded Ceramic Thermal Barrier Coatings", ASME Transactions, Journal of Engineering Materials and Technology, Vol. 119, pp. 148-152, April 1997.

K. Kokini, B.D. Choules and Y.R. Takeuchi, "Thermal Fracture Mechanisms in Ceramic Thermal Barrier Coatings", Journal of Thermal Spray Technology, Vol. 6(1), pp. 43-49, March 1997.

B.D. Choules and K. Kokini, "Architecture of Functionally Graded Ceramic Coatings Against Surface Thermal Fracture", ASME Transactions, Journal of Engineering Materials and Technology, Vol. 118(4), pp. 522-528,1996.

K. Kokini and B.D. Choules and Y.R. Takeuchi, "Surface Thermal Cracking of Thermal Barrier Coatings due to Stress Relaxation: Zirconia vs. Mullite", Journal of Surface and Coatings Technology, Vol. 82, pp. 77-82, 1996.

Professor Kokini's research area involves the fundamental understanding of the deformation and fracture processes of high temperature materials such as ceramic coatings deposited on metallic substrates. In particular, he performs controlled experiments where the surface of the coating is subjected to a high heat flux generated by a 1.5 kW C0₂ laser. The effect of heating and cooling the specimens are modeled, usually using the finite element method. The objective is to determine the mechanisms which lead to different thermal fracture modes. These mechanisms include surface cracking, interface cracking and edge cracking. The models developed are used to perform parametric studies which would lead to the design of a coating/substrate system and processing methods that would result in the longest possible life. Similar approaches can also be used for polymeric coatings on different substrates.

Professor Kokini's work on high temperature materials made of layers of ceramics and metals combines controlled high heat flux experiments with analysis that aims at relating micromechanical aspects such as interface topology to the micromechanical design such as thickness of the coating, the applied thermal load etc. Therefore, the methodology and criteria for optimizing the design and use of a structure such as a machine tool, piston, turbine blade etc. made of a multilayer material system are developed. The study of the behavior of interfaces subjected to thermal loads is expected to result in new material systems which can withstand larger thermal and mechanical loads. In particular his research is expected to yield design methodologies for functionally graded composite system. The same information can also be used to explore methods which would allow easy removal of coatings from surfaces using thermal and mechanical loadings.

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