⒈ physical tempered glass, also known as hardened tempered glass. It is the ordinary flat glass in the heating furnace heated to near the glass softening temperature (600 ℃), through its own deformation to eliminate internal stress, and then remove the glass furnace, and then the long nozzle high pressure cold air blown glass Both sides, so that it quickly and evenly cooled to room temperature, can be made of tempered glass. This glass is in the internal tension, the external pressure of the state of stress, once the local damage occurs, there will be stress release, the glass was broken into numerous small pieces, these small pieces of sharp edges and corners are not easy to hurt.
⒉ chemical tempered glass by changing the chemical composition of the glass surface to improve the strength of the glass, the general application of ion exchange method is tempered. The method comprises the following steps: immersing the silicate glass containing alkali metal ions in lithium (Li +) salt in molten state to exchange Na + or K + ions with Li + ion in the glass surface to form Li + ion exchange layer on the surface; The expansion coefficient is smaller than that of Na + and K + ions, resulting in smaller shrinkage of the outer layer and larger shrinkage of the inner layer during cooling. When cooling to normal temperature, the glass is also in a state of being tensioned in the inner layer and compressed in the outer layer, Similar to physical toughened glass.