Elastic stress transfer from fiber to coating in a fiber-coating system

Effects of Friction in Ceramic Coating/Fiber Composites

“…The major system in the present analysis has the following parameters: E' = 320 GPa, v = 0.2 and a = 3.0 x 10-6/ °C in the coating; Ef = 400 GPa, vf = 0.2, and af = 2.0 x 10-6/°C in the fiber; relative coating thickness, (b -a)la, is 0.1; relative coating length, 211a, is 20; and temperature change, T, is -500°C. The effects of Young's modulus and Poisson's ratio on the stress transfer are discussed in a separate paper [19].…”

“…Re-evaluate Equation (19) with a boundary condition that QZ(s) = Qz at the intercept of the slip and no-slip region. The stresses in the non-slip region can thus be given as…”

“…Residual stresses are assumed to be induced by thermomechanical mismatch. Intrinsic residual stresses by processing (e.g., due to inhomogeneous sintering rate) are discussed in a separate paper [19]. The stress transfer under non-slip condition as well as partial slip condition is studied.…”

“…Firstly, the frictional interaction, according to the simple Coulomb friction law, between the fiber and the matrix is studied by choosing a simple system which consists of a single fiber and a thin coating on its central region ( Figure 1) [18,19]. Critical loads for complete sliding, maximum axial stresses in the coating and the interfacial normal and shear stresses are calculated when the system is subject to thermal residual stresses and external tensile loads at the fiber ends.…”