Elastic Instability of Pseudo-Elastic Rubber Balloons

摘要

Elastic instability for the inflation and deflation of a thin-walled spherical rubber balloon is examined within the framework of finite pseudo-elasticity. When a spherical rubber balloon is inflated, it is subject to a complex deformation after a pressure maximum has been obtained. One part of the balloon is lightly stretched while the remainder becomes highly stretched. So an aspherical deformation is observed after the initial spherical inflation. A pseudo-elastic strain energy function including a damage variable which may model the loading, unloading and reloading of rubber is used. The balloon is idealized as an elastic membrane and the inflation, deflation and re-inflation of the balloon is described in detail. Instability of solutions is discussed through energy comparison. Furthermore, the effect of temperature is discussed with a thermo-hyperelastic model and the residual strain is analyzed with a pseudo-elastic strain energy function including a residual strain variable.