Residual thermal stresses in functionally graded Ti-TiC_x materials.

Graded Ti-TiC nanoscale multilayers transform after an appropriate interdiffusion anneal into a functionally graded (FG) region between a TiC hard coating and a Ti substrate. Using the available database regarding the properties of the TiCx solid solution, it was possible to develop analytical expressions for the residual thermal stresses that develop in the FG-material. It was shown that by appropriate design of the graded concentration in the initial multilayer, it is possible to generate compressive stresses in the vicinity of the ceramic-like edge of the FG- transition zone.