Effect of surface tension and geometry on cavitation in soft solids

Unbounded growth of cavity in soft solids subjected to internal pressure is a commonly observed phenomenon. Such phenomenon has been harnessed by developing cavitation rheology technique (CR) to investigate the local mechanical properties of many complex soft materials. The elasticity of the material, surface energy, and geometric factors in combination can dictate the cavitation behavior in a complex manner. We report a finite element based framework capturing the coupled effect of elastic strain energy and surface tension on the cavitation phenomenon. We show results for a spherical cavity in an infinite elastic media and for the CR geometry. The surface tension is shown to increase the critical pressure for cavitation. The energy release rate also depends on the surface tension. In CR geometry, by varying the distance between the needle and the immovable sample boundaries, we have captured the conditions leading to confinement. Our results provide new understanding regarding the effects of geometry and surface tension on the cavitation phenomenon in soft solids.