The Interfacial Structure Modulation And Mechanical Properties Of Organic-inorganic Glass Laminates

Organic-inorganic glass Laminates are transparent composites, consisting ofglass and transparent organic materials laminated with an adhesion interlayer. It canmeet both the characteristics of high hardness of inorganic glass and thecharacteristics of light of the organic glass at the same time, widely used in aerospacefield. With the application and development of the material, however, it has exposedsome new problems in actual use. The main problem is the interface failure, whichresults in the poor reliability and the reduced lifetime of glass laminates.In this paper, the effects of interface microstructure on organic and inorganiclaminated glass and microscopic mechanism were studied, by optimizing the interfacestress distribution state, reducing the interfacial shear stress, then improving theinterface bonding strength. First of all, the organic glass is cheated by mixed acidcorrosion and hydrothermal corrosion method, effects of the corrosion microstructureon its optical properties and mechanical properties were analyzed, the best process oftreating was obtained by comparing the results from these two methods. Secondly,effects of interface structure on the optical properties and the mechanical properties ofthe laminated glass were studied under different hot-pressing conditions. Finally,effects of the interface structure on the optical properties and mechanical propertieswere studied under the service performance conditions, combined with thenondestructive testing, analysis the microscopic mechanism of interface failure underthe hygrothermal aging conditions.The results of mixed acid corrosion show that with the extension of corrosiontime, the weightlessness rate and the corrosion depth of the glass increases linearly;the corrosion rate gradually decreases and tends to be stable; the size of etch pitsfirstly increases and then decreases, with the inverse tendency for the uniformity ofetching pit distribution; the transparency firstly decreases then increases; the bendingstrength firstly increases then decreases and tends to be stable. The optimumtreatment processing can be obtained: the best mass proportion of mixed acid etchingsolution is4:1[m(HF/H2SO4)], the corrosion time is20min. The results shows that theuniformly distributed pit size, the maximum contact angle of71°and the minimumfracture toughness of5.8nm are achieved, as well as the maximum bending strengthof174MPa, respectively. The results of hydrothermal corrosion experiments show that with increasing thecorrosion temperature, the weightlessness rate and the corrosion rate of the glassincreases linearly; the transparency decreases; the bending strength and the hardnessfirstly increase, then remain, last decrease; the fracture toughness remains in a certainrange fluctuations. With increasing the corrosion time under the same temperature, theweightlessness rate and the corrosion rate of the glass increase; the contact anglefirstly increased and then drops; the transparency, bending strength and impactstrength firstly increase and then decrease. The optimum technology is the etchingtime of soda-lime silicate glass is20min and the temperature of hot-pressing processis120℃.The results shows that the maximum of the shearing strength is7.3MPa,the maximum transparency of87.8%and the minimum haze of2.4%are achieved,respectively. Mixed acid corrosion, with its simple condition as well as easy to control,is prior to the hydrothermal corrosion.With the corrosion time prolongs, the transparency and the shear strength oflaminated glass firstly increase then decrease, the haze increases and tends to be stable.With the hot-processing temperature increases, transparency firstly decreases thenincreases，shear strength increases. With increasing the heat temperature of the glass,shear strength of laminated glass firstly decreases then increases，transparencyremains in a range. We obtain the optimum technology, which is the etching time ofsoda-lime silicate glass is20min and the temperature of hot-pressing process is120℃with its press is1.2MPa.The results shows that the maximum of the shearingstrength is7.3MPa, the maximum transparency of87.8%and the minimum haze of2.4%are achieved, respectively.With the aging time increasing, the interface shear strength of the laminated glassincreases, the transparency decreases. As the aging time is28d, the maximuminterface shearing strength value of the laminated glass is11.1MPa. Under theultraviolet aging conditions, as the etching time of glass prolongs, the interfaceshear strength and the transparecy of laminated glass firstly increase then decrease.To sum up, we can significantly improve the interface bonding performance oflaminated glass, improve the aging performance of the interface of laminated glassunder the under the hygrothermal aging conditions through regulating the glasssurface microstructure, optimizing the interface of laminated glass structure. It has animportant theoretical reference value for developing the lightweight andhigh-performance organic-inorganic laminated glass. As the etching time of the soda-lime silicate glass is20min, the maximum shearing strength of the ultravioletaging laminated glass attains5.5MPa, and the maximum transparency of theultraviolet aging laminated glass achieved87.1%.