Influence Of Cover Composition Design And Properties Based On Two-stepchemical Strengthened Process

In this paper,alkali aluminum silicon glass is taken as the research object,and two-step molten salt chemical strengthening process is used to strengthen the glass.On the basis of alkali-alumina glass,five sets of oxides of Li₂O,MgO,ZnO,B₂O₃ and P₂O₅ are added to the glass,and the transparent and impurity-free glass products are melted at 1640?,cast,annealed,cut,and polished.The influence of glass composition on CS?CS,Compressive Stress?,DOL?DOL,Depth of layer?and impact strength,as well as the linear thermal expansion coefficient,surface tension and viscosity parameters of glass after two-step molten salt chemical strengthening were systematically investigated.The results show that:The performance of glass chemical strengthening does not increase with the increase of Li₂O in the glass composition.Li⁺has its particularity?having a small ionic radius and large field strength?,and it is recommended that the composition is less than 5wt%.Adding a small radius and strong field external body MgO and ZnO in the glass can greatly increase the CS after chemical strengthening of the glass.After adding MgO,CS increases by 70%,and after adding ZnO,CS increases by 47%,but DOL will decrease.Adding the network forming body P₂O₅ to the glass can simultaneously increase the glass CS and DOL by more than 25%.The effect of glass chemical composition on the impact strength of glass after two-step molten salt strengthening.Adding MgO,ZnO and P₂O₅ to glass can improve the glass impact strength after chemical strengthening.Among them,MgO and ZnO can increase the glass impact strength by 60%.Above,P₂O₅ can improve the impact strength by 17%,and adding 5wt%or less of MgO,ZnO,and P₂O₅ to the glass composition can improve the glass impact resistance.The chemical composition of the glass has an important influence on the thermal expansion coefficient,surface tension and viscosity of the wire.The linear thermal expansion coefficient of alkali alumina silicate glass is closely related to glass composition and network structure.The effect of the coefficient of thermal expansion of glass fiber is as follows:Li₂O>ZnO>B₂O₃>MgO>P₂O₅,where Li₂O,ZnO and MgO increase the expansion coefficient,and B₂O₃ and P₂O₅ decrease the expansion coefficient.The composition of glass can be designed according to this law.Composition has a complex effect on surface tension.With the increase of the content of strong network outer body with small radius field,the surface tension of glass increases,and the network formation body can reduce the surface tension of glass.Glass viscosity has guiding significance for glass production and processing.Adding monovalent alkali metal to glass can reduce the overall viscosity of glass.Adding divalent alkali metal MgO and ZnO can reduce the high temperature viscosity of glass and increase the medium and low temperature viscosity.