What is semi-tempered glass

Semi-tempered glass is also called heat-strengthened glass. Semi-tempered glass is a type between ordinary flat glass and tempered glass. It has some advantages of tempered glass. For example, its strength is higher than that of ordinary float glass, which is twice that of ordinary float glass. At the same time, it avoids the flatness of tempered glass. Poor quality, easy to self-explode, and once destroyed, it will be crushed as a whole and other unsatisfactory shortcomings. When the semi-tempered glass is damaged, it will crack radially along the crack source, and generally there is no tangential crack propagation, so it can generally remain intact after damage.

Single-piece semi-tempered glass (heat-strengthened glass) is not a safety glass, because once broken, large fragments and radial cracks will be formed. Where human impact may occur.

The difference between tempered glass and semi-tempered glass

Tempered glass is annealed glass through high temperature and quenching, forming a strong compressive stress on the surface, which increases the mechanical strength of the glass several times, that is, tempered glass. The surface stress of tempered glass is: 69~168 Mpa. It is characterized by broken small obtuse-angle particles, which will not cause major harm to the human body. The strength is 4 times and above that of ordinary glass. It has good thermal stability, and the temperature difference that ordinary glass can withstand after tempering is about 180°C. The disadvantage of tempered glass is that it is easy to explode and has poor flatness.

Semi-tempered glass is annealed glass through high temperature and quenching, and the surface layer forms a compressive stress lower than 69 MPa, which increases the mechanical strength of the glass several times, that is, semi-tempered glass. The surface stress of semi-tempered glass is: 24-69 Mpa. After being broken, it is the same as ordinary glass, and the product is characterized in that the strength of semi-tempered glass is more than 2 times that of annealed glass. Safety: When broken, the fragments are radial, and each fragment extends to the edge, which is not easy to fall off and is relatively safe, but it does not belong to safety glass. Deflection: The deflection of semi-tempered glass is smaller than that of tempered glass and larger than that of annealed glass. Thermal stability: The thermal stability is also significantly better than that of annealed glass, and the temperature difference that ordinary glass can withstand after semi-tempering is about 75°C. Semi-tempered glass will not explode.

The use of semi-tempered glass

Semi-tempered glass is suitable for curtain walls and exterior windows in buildings, and can be made into coated glass, and its image distortion is better than that of tempered glass.