Chemomechanical analysis for interfacial reactions between γ-TiAl alloy and glass-ceramic coating in micro/nano scale

To simulate interfacial reactions process and deformation in γ-TiAl and glass-ceramic coating system at high temperature, we developed a coupled chemomechanical model with chemical reactions, diffusion, and mechanical deformation incorporated. Tensile radial and circumferential stresses develop in interfacial zone and coatings as the interfacial reactions occur. Tensile radial stress could tear coatings off alloys while the tensile circumferential stress could result in crack initiation and propagation, even spalling of coatings. The bulk radial stress can be markedly reduced by taking the surface effect into account. Consequently, tensile radial stress vanishes in alloy-coating system on nano scale.