Tempered glass is a type of prestressed glass. In order to increase the strength of the glass , chemical or physical methods are usually used to form compressive stress on the surface of the glass. When the glass is subjected to external force, the surface stress is first offset, thereby improving the bearing capacity and enhancing the wind resistance of the glass itself. Compressive, cold and hot, impact and so on.    

Tempered glass is a deep-processed product of ordinary glass. It is a uniform heating of ordinary glass at a high temperature of 600-700 degrees, and it is rapidly cooled. Like steel quenching, a uniform and compact compression layer is formed on the surface of the glass, just like putting a glass on it. The invisible steel armor increases the strength of the glass. After tempering, the internal stress of the glass reaches equilibrium, and the molecules are in a state of tension. As long as one place destroys the entire equilibrium state, it will collapse and the whole glass will collapse. Therefore, the tempered glass can no longer be cut and processed. The glass is processed to the desired shape before tempering, and then tempered. Therefore, when manufacturing tempered glass, it is necessary to set the size and shape before processing.

Chemical tempering utilizes the ion transport and diffusion characteristics of the glass surface to change the composition of the surface area of the glass (typically within a few hundred micrometers). This change causes the microcracks on the glass surface to disappear or form a compressive stress layer on the surface of the glass, thereby making the glass strength improve. Factors affecting the strength of chemically tempered glass:

1. Glass composition: Generally, the SiO2 content of glass is 60-65% . Al2O3 accelerates during the ion exchange process, and the appropriate amount of Al2O3 is 1% to 17% . When the content is less than 1% , the chemical stability of the glass is poor, and when the content is more than 17% , the raw material is difficult to melt when the glass is produced.

2 , molten salt ingredients: KNO3 ingredients the purer the better. More than 0.5% of Na2O impurities will have an effect on the tempering effect. New dissolved salts must be replenished in time and the salt ponds should be cleaned in time.

3 , treatment temperature: must use the appropriate temperature, too low ion exchange can not be carried out, too high will cause the glass structure to relax, so that the strength is reduced.

4 , treatment time: the appropriate ion exchange time must be used, the glass is more chemically tempered, the longer the treatment time, the greater the intensity, but the benefits generated by too long is not obvious.