Preparation And Property Research Of Engineered Stress Profile Glass

Engineered Stress Profile glass(ESP glass)is a sort of silicate glass with specially designed stress profile,which can be implemented by ion exchange or thermal tempering.The fracture of ESP glass has two features: 1)multi-crack behavior before fracture;2)narrow distribution of fracture strength.The excellent strength stability of ESP glass indicates great application prospect in field of mechanical sensor and safety engineering.Especially,ESP glass has become an imperative requirement as core mechanical sensing component in inertial sensing device.The research dedicates to developing a process method which can stably produce ESP glass with high strength and strength Weibull modula and promoting its application in inertial sensing device.ESP glass was prepared by two-step ion exchange.The research studied the preparation,characterization of ESP glass and its application in inertial sensing device.The research contents and results are shown as follows:1.The diffusion process was simulated by using FDTD method.The dependence of potassium ion concentration profile on the second step exchange time was studied.Accordingly,the process parameters were determined.2.Optimal melting salt composition and processing time were determined by bending strength test.The Weibull modula of the prepared ESP glass peaked at 54.51.The strength performance was analyzed combined with the potassium ion profile.The hardness and toughness of the untreated glass,one-step ion-exchanged glass and two-step ion-exchanged glass were compared by indentation tests.Dense and radial cracks were observed on the two-step ion-exchanged glass.The diffusion process in vacuum was simulated.Based on the simulation,the degeneration of the strength stability was estimated.3.An inertial sensing devices with property of reliable fracture subjected by impact in universal directions were designed by using ESP glass as core sensing components.The stress profile of the glass components was solved based on principles of material mechanics.The directions of the applied acceleration whose value was fixed were calculated when the tensile stress at the fixed ends of the glass components' reached extreme values.The allowable range of glass strength was calculated by finite-elment simulation.The required minimum Weibull modula was calculated based on Weibull statistical analysis.Accordingly,the potential application of ESP glass in inertial sensing devices was verified.