Tempered glass is a glass that is heated to a softening temperature and then uniformly and rapidly cooled, so that the glass surface obtains compressive stress. During the cooling process, the exterior of the tempered glass solidifies due to rapid cooling, while the internal cooling is slow. When the interior continues to cool and shrink, compressive stress is generated on the glass surface, and internal tensile stress is generated, thereby improving the glass strength and thermal stability.
1. High strength
Compared with ordinary glass of the same thickness, toughened glass has 3-5 times higher bending strength and impact strength. When the ordinary glass is bent under load, the upper surface layer is subjected to compressive stress, and the lower surface layer is subjected to tensile pressure. The tensile strength of the glass is low. If the tensile strength is exceeded, it will break, so the strength of the ordinary glass is very low, and when the tempered glass is loaded, The maximum tensile stress is not located on the glass surface like ordinary glass, but in the center of the tempered glass plate, so the tempered glass does not crack under the same load.
Tempered glass produces compressive stress through quenching, which improves the strength of the glass, so the glass is not easy to break when impacted. Even when the load is broken, the fragments are in a small obtuse angle state, which hardly causes harm to the human body. When ordinary glass is broken, it is a sharp large piece, which is easy to cause serious harm to the human body.
3. Thermal shock
Tempered glass has a relatively high thermal shock resistance. Compared with ordinary glass of the same thickness, the thermal shock resistance is 3 times higher. The abrupt temperature range of tempered glass can be 220℃-250℃, while ordinary glass is only 70℃-100℃. When the tempered glass is subjected to a certain quenching temperature, the compressive stress on the surface is opposite to the tensile stress, which cancels each other out; when it is hot, the upper surface generates pressure. Since the compressive stress of the glass is 10 times the tensile stress, the tempered glass also Can withstand a certain sudden heat temperature. Tempered glass can resist a certain temperature mutation, so it can play a temporary role in fire protection in the event of a fire.