Research On The Processing Mechanism And Process Optimization Of 3D Ultra-thin Glass Molding

With the development of aerospace,military,medical and 3C industries,the design of aspherical optical component has attracted more and more attention.As a substitute for the traditional manufacturing process for glass materials,the glass molding process?GMP?has the advantages of high forming accuracy,short production cycle,low cost and non-pollution.Currently,there are still many technical problems of GMP to be solved.For example,the problems of large residual stress,low yield and high energy consumption.These technical difficulties that hinder the further development of the technology.Therefore,the further research and analyze on the mechanism and process of glass molding process is necessary.In order to improve the molding quality of glass component and reduce the production energy consumption,based on the stress relaxation and structural relaxation models of glass material,a numerical simulation model of the multi-station molding process for the optical component of smart phone cover plate is established.The temperature distribution,residual stress,shape deviation and production energy consumption of glass component are predicted.The simulation results show that the high stress?greater than 10MPa?mainly distributed around the holes and bent area of the glass component,and the maximum shape deviation appeared in the middle of the glass component.And combined with the orthogonal experimental design and NSGA-III optimization algorithm,the influence of process parameters?heating rate,holding time,molding temperature,molding pressure and cooling rate?on the residual stress,shape deviation and energy consumption in the molding process was analyzed.The results show that molding temperature,cooling rate and molding pressure are the main factors affecting the residual stress and shape deviation,while molding temperature and heating rate are the main factors affecting energy consumption.And effectively reduce the maximum residual stress and shape deviation of the molded product,balance the relationship between the molding quality and energy consumption,and obtain the optimized process schemes with low residual stress,shape deviation and energy consumption.Through experimental verification,the average prediction error is less than 20%,which further verifies the validity of the model.In order to further solve the problem of high energy consumption in the molding system,a numerical model of heat conduction between heating plate,heat conducting plate and mold was established,the temperature distribution and energy flow of the mold were predicted,and the influence of different mold structure,heating rate and heat flux configuration on the energy consumption of the heating&soaking stage was studied.The results show that the energy generated by heating device,adopting optimized molds?I?,is 614.0 kJ,which was reduced by 6.43%compared with the original model?656.2kJ?.Meanwhile,based on the optimized molds?I?,the energy generated by heating device in GMP were 594.4 kJ and 608.0kJ by optimizing heating rate and heat flux density,which was decreased by 3.19%and 0.98%,respectively.Finally,by analyzing the minimum CO₂ emissions of the energy consumption optimization model of mold structure,heating rate and heat flux density,it can be found that the minimum annual CO₂ emissions in GMP heating stage was 31,957.6kg,which is decreased by 9.4%compared with the original model,which is of great significance to realize green manufacturing and sustainable development.