What is semi-tempered glass

Semi-tempered glass is also called thermally strengthened glass. Semi-tempered glass is a variety between ordinary flat glass and tempered glass. It has some of the advantages of tempered glass. For example, the strength is higher than ordinary float glass, which is twice that of ordinary float glass while avoiding the flatness of tempered glass. The disadvantages of poor temperature, self-explosion, and crushed as a whole once destroyed. When the semi-tempered glass is damaged, it cracks radially along the crack source, and generally has no tangential crack propagation, so it can still keep the whole body without collapsing under normal circumstances.

Single piece of semi-tempered glass (heat-strengthened glass) is not safety glass, because once it is broken, it will form large fragments and radial cracks.Although most of the fragments do not have sharp corners, they can still hurt people and cannot be used for skylights and glass. Where human body 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 obtuse-angled particles after rupture, which will not cause major harm to the human body. The strength is 4 times or more than the strength 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, the surface layer forms a compressive stress of less 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. The product feature is that the strength of semi-tempered glass is more than twice that of annealed glass. Safety: When broken, the fragments are radial, and each fragment extends to the edge. It is not easy to fall off and is safer, but it is not safety glass. Deflection: The deflection of semi-tempered glass is smaller than tempered glass and larger than annealed glass. Thermal stability: The thermal stability is also significantly better than that of annealed glass. The temperature difference that ordinary glass can withstand after being semi-tempered is about 75°C. Semi-tempered glass will not explode.

Use of semi-tempered glass

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