Tempered glass, also known as tempered glass. It is a physical or chemical method, in the glass surface to form a compressive stress layer, the glass itself has a high compressive strength, will not cause damage. When the glass by external force, the pressure layer can be part of the tensile stress offset, to avoid the fragmentation of glass, although the glass inside the larger tensile stress state, but the glass inside the defect-free existence, will not create damage , So as to achieve the purpose of improving the glass strength. It is a secondary processing of flat glass products, tempered glass processing can be divided into physical steel and chemical steel chemical method.
Physical tempered glass is also called hardened tempered glass. It will be ordinary flat glass in the furnace heated to near the glass softening temperature (600 ℃), through its own deformation to eliminate internal stress, and then remove the glass out of the furnace, and then use high-pressure nozzle blowing high-pressure cold air to the glass Both sides, so that it quickly and evenly cooled to room temperature, can be tempered glass. The glass is internally tensioned, externally stressed, and when locally damaged, stress is released and the glass is broken into numerous small pieces that are not sharp and sharp.
Chemical toughened glass is to change the glass surface of the chemical composition to improve the strength of the glass, the general application of ion exchange for steel. The method comprises the following steps: immersing a silicate glass containing alkali metal ions into a lithium (Li +) salt in a molten state to exchange Na + or K + ions of the glass surface layer with Li + ions to form a Li + ion exchange layer; The expansion coefficient is less than Na +, K + ions, resulting in the cooling process of the outer layer of contraction caused by smaller and larger inner contraction, when cooled to room temperature, the glass is also in the inner tension, outer pressure state, Similar to physical tempered glass.