Study on the Punching Creep Behavior of <scp>PA56</scp> /512 Biaxially Stretch Film

ABSTRACT This study investigates the creep behavior of PA56/512 biaxially oriented films during the stamping process, employing a self‐developed film stamping device and fractional rheological theory. Using a universal tensile testing machine, experiments were conducted to analyze the effects of varying loads and loading rates on the stamping depth, viscoelasticity, and viscoplastic deformation. A fractional Burgers model was derived to describe the stamping deformation of the films, allowing for the fitting and analysis of creep curves under different conditions. Dynamic flow variables, including storage compliance, loss compliance, and loss factor, were calculated from the model. The results reveal that increased load enhances the viscous flow and promotes the transition from viscoelastic to viscoplastic deformation, while a higher loading rate inhibits viscous flow. Additionally, the fluidity in the viscoelastic region surpasses that in the viscoplastic region during the stamping process. These findings offer insights into the stamping deformation mechanism of biaxially oriented films and provide theoretical guidance for the production of high‐performance aluminum‐plastic films.