The glass molding process (GMP) can press glass perform into a shape of finished lens under high pressure and temperature conditions, and it is easy to achieve mass production. So, it has emerged as a promising alternative way to produce complex shapes lens. It is well known that viscoelastic is one important properties of glass at high temperature. In this study, A 4-pair generalized maxwell model was used to express viscoelastic of glass, and model parameters were obtained by fitting the relaxation curve obtained from experiment.
The finite element models were established by MSC.MARC, the correctness of the FEM models and its used model parameters were verified by the cylindrical compression experiments. Finally, the simulations of glass lens forming stage were performed under different conditions. Stresses distribution were predicted by FEM, it was found that the maximum stress at the edge of lens, which make lens rupture easily at this zone. It was also discovered that the molding temperature is higher, the less stress, and the molding velocity is higher, the higher stress.
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