Polyvinylidene fluoride (PVDF) is an engineering thermoplastic having a high degree of sensibility to crack, which affects long-term mechanical behavior. This study evaluates the crack-sensitive of PVDF for one commercial-grade through the development of a numerical model.
Firstly, tensile tests using DIC were performed on both uncrack and pre-crack specimens to get experimental tensile as DIC-displacement, displacement-control, and load data. For pre-crack specimens, it was proposed two values of depth: 1.0 and 1.5 mm, opened by razor blade. All specimens were uniaxial tests at 23°C under 5 mm/min. Secondly, tensile tests using extensometer were implemented for uncrack samples to determine material parameters for calibration of the numerical model and comparison with DIC-displacement. Finally, a numerical model based on the FE was implemented using ANSYS-student that inputs PVDF’s material properties, which considered the elastic-plastic behavior in simulation tests.
The PVDF demonstrated significant crack sensitivity, as it can be seen in experimental and numerical data. And, the numerical model developed based on MKHP was successfully agreement against experimental data obtained by Blue Hill 3 software. Therefore, the results allowed us to observe that pre-crack acts as a stress concentration and the numerical model got well simulates this influence on the PVDF mechanical behavior.