Analysis of thermal cavitation in a viscoelastic composite sphere under a uniform temperature field

Cavity bifurcation is an important mechanism of damage and fracture failure of various materials. The thermal cavitation problem of a composite sphere composed of two kinds of viscoelastic materials subjected to a uniform temperature field was studied in this paper. Based on the finite deformation dynamics theory, a nonlinear mathematical model describing cavity movement in a composite sphere was established by employing the Kelvin–Voigt constitutive equation of thermo-viscoelasticity. Adopting the dimensionless transformation, a parametric cavitated bifurcation solution describing the cavity radius with the temperature was obtained. The dynamic variation curves of the cavity radius, which increase with external temperature, radius ratios, and material parameters, were also discussed. It was proved that the dynamic growth of an infinitely large sphere, including a small sphere, can be achieved by a finitely composite sphere.