Mechanism of springback behavior in ultra-thin glass molding process: A molecular dynamics study

Springback behavior is the core reason accounting for the low geometry accuracy of the glass molding process, especially for the ultra-thin glass. But the mechanism of springback remain unrevealed because of the challenge in observing or measuring the ultra-thin glass inside the mold by experiment. Therefore, we establish a molecular dynamics model to simulate the glass molding process and the following springback behavior, which provides an atomistic view of the displacement during the unmolding process. Three specific positions along the ultra-thin glass are picked to study the springback behaviors at different places. According to the simulation results, we find that two factors govern the springback behavior: the force factors contributed by residual stress, friction and adhesion, which will lead to the elastic and plastic deformation and the temperature factor, namely the temperature difference between the top and bottom surface of the glass. At last, we perform a series of simulations to study the effects of pressure and temperature on the springback behavior. This study helps reveal the springback behavior at atomic level and provides some practical instructions on the ultra-thin glass molding process.