Effect of Novel Thermo-Chemical Treatment on Bending Strength of Laminated Glass

The science of thermal and chemical treatment of glass is well documented. The Laminated Glass (LG) is usually not treated as either treated glass is used during production or lower melting temperature of interlayer does not allow the treatment. The present work reports the novel methods of thermo-chemical treatment of LG having annealed soda lime glass plies. Five thermo-chemical treatments were performed on LG using different salts (Potassium Nitrate Carbohydrazide, Lithium Nitride), via clay coating (saturated with salts), using fused silica wafer coated with a thin graphene layer and utilizing the microwave heating. The bending strength is measured before and after thermo-chemical treatment using Q-set coupled bending tester (following the ASTM D790-03). The linear elastic model is utilized for obtaining normal stress and deformation at fracture load using ANSYS 14.5. The bending strength of thermo-chemical treated LG sample was found significantly higher than untreated LG in the most cases. The fracture pattern of the treated LG was also modified compared to the untreated LG as impurities and defects were reduced during treatment. The mechanics of increased bending strength and modified fracture is also discussed with reference to the effects of thermo-chemical treatment of LG, however, the need of a specialized numerical method that can effectively model the implications of treatment on LG and multiple fractures experienced by the LG during testing are suggested as future work.