Numerical Simulation and Experimental Study of Crack Propagation of Poly dim ethylsiloxane

摘要

Polydimethylsiloxane (PDMS) is applied in a wide range of application fields, due to its flexibility, transparent nature, biocompatibility, low cost, etc. Accordingly, it is a very versatile and useful soft polymeric material. However, some applications are severely limited because of its brittleness. Therefore, it is very important to study the fracture characteristics of PDMS. In this ■ study, Neo-Hookean model and Arruda and Boyce model are applied to numerically investigate the crack propagation of three different types with pre-cut cracks. The three types of specimens with pre-cut crack and one type of intact specimen are prepared for tensile test. Meanwhile, high-speed camera is used to record the whole crack propagation during the tensile process. By comparing with the simulation results and experimental results, it is found that Neo-Hookean model and Arruda and Boyce model can satisfactorily be used to simulate the deformation of PDMS. Furthermore, the fitting parameters in the models are very close to the parameters determined experimentally. According to experimental tests, we obtain that the facture energy of PDMS is around 1310 J/m~2. The cracks present bluntness before propagation and then quickly propagate to rupture in less than 1 second. In addition, edge crack is the most sensitive type for PDMS among three different cracks.