Chemically tempered glass is mainly made of glass with a thickness less than 3mm. Chemically tempered glass can improve the strength of glass by changing the chemical composition on the glass surface, and generally it is tempered by ion exchange method. In this method, silicate glass containing alkali metal ions is immersed in molten lithium (Li+) salt, so that Na+ or K+ ions on the glass surface are exchanged with Li+ ions, and a Li+ ion exchange layer is formed on the surface. Because the expansion coefficient of Li+ is smaller than that of Na+ and K+ ions, the outer layer shrinks less while the inner layer shrinks more during cooling. When the glass is cooled to normal temperature, it will also be stretched in the inner layer.

The technological process of chemically toughened glass is as follows:

White sheet finished product -QC inspection-cleaning treatment-chemical tempering-heat preservation and cooling-cleaning and drying-packaging. Because of the slow exchange rate of potassium and sodium ions, it takes 1-8 hours to make the glass have a large stress value and a stress layer thickness that meets the requirements of use.

Advantages of chemically toughened glass:

Chemical tempered glass has not been subjected to high temperature process with humidity above, and will not warp like physical tempered glass. The surface smoothness is the same as that of the original glass, but the strength and temperature resistance are improved to a certain extent, so it can be cut properly.

Chemically tempered glass has high strength, and its compressive strength can reach more than 125MPa, which is 4 ~ 5 times larger than that of ordinary glass. The impact strength is also high. When measured by steel ball method, 0.8kg steel ball falls from the height of 1.2m, and the glass can be kept intact. The elasticity of chemically tempered glass is much greater than that of ordinary glass. A piece of tempered glass with 1 200 mm× 350 mm× 6 mm can have a bending deflection of 100mm after being stressed. When the external force is removed, it can still be restored to its original state, while the bending deformation of ordinary glass can only be a few millimeters. Thermal stability is good, and it is not easy to crack when it is rapidly cooled and heated, which is another feature of chemically tempered glass. This is because the compressive stress of chemically tempered glass can offset part of the tensile stress caused by rapid cooling and rapid heating. Chemically toughened glass is resistant to thermal shock, the maximum safe working temperature is 288℃, and it can withstand the temperature difference change of 204℃.

Chemically toughened glass is suitable for the following construction occasions: occasions where there are requirements for reducing self-weight, impact strength, bending strength and cold and hot impact resistance, such as windows and ceilings in agricultural greenhouses, door and window glasses in mobile homes, etc.