[Knowledge] How is glass tempered?

Tempered glass is actually a kind of pre-stressed glass, in order to improve the strength of the glass, usually using chemical or physical methods, the formation of compressive stress on the surface of the glass, the glass is subjected to external forces to offset the surface stress first, so as to improve the load-bearing capacity, improve the tensile strength of the glass.

　There are two main advantages of tempered glass, the first is the strength of ordinary glass several times, bending strength is 3 to 5 times the ordinary glass, impact strength is 5 to 10 times the ordinary glass, improve the strength of the same time also improves the safety. The use of safety is the second main advantage of tempered glass, its increased carrying capacity to improve the fragile nature, even if the destruction of tempered glass is also a small fragments without sharp edges, the harm to the human body has been greatly reduced. Toughened glass is resistant to rapid cold and heat properties compared to ordinary glass has 2 to 3 times the improvement, generally can withstand temperature changes of more than 150LC, to prevent thermal cracking has a significant effect.

　　Tempered glass is processed from ordinary plate glass or float glass. Ordinary flat glass requires special selection or first-class products; float glass requires superior or first-class products.

　　The production of tempered glass process has two kinds: one is the ordinary flat glass or float glass in specific process conditions, by quenching or air-cooled quenching method of processing and processing. The other is ordinary flat glass or float glass through the ion exchange method, the glass surface composition changes, so that the glass surface to form a layer of compressive stress layer processing and processing.

　　Tempered glass has high impact strength (4 to 5 times higher than ordinary plate glass), high bending strength (5 times higher than ordinary plate glass), good thermal stability, as well as smooth, transparent, cuttable and so on. In the event of super impact damage, the fragments are dispersed fine particles, no sharp edges, so it is also known as safety glass.

　　Tempered glass is divided into flat tempered glass and curved tempered glass by shape. Plane tempered glass thickness of 4, 5, 6, 8, 10, 12, 15, 19mm eight; curved tempered glass thickness of 5, 6, 8mm three.

　　Tempered glass is divided into two categories according to the quality of its appearance: superior products, qualified products.

　　Tempered glass is divided into: Class I, Class II and Class III according to its fragmentation status.