Tempered Glass

Tempered Glass is made by heating flat glass to just below its softening temperature and suddenly chilling it with jets of cold air. Resulting in a powerful compressive stress layer on the outer skins, while the interior with severe tensile stress. Consequently, the impact applied to the glass will be offset by the compressional stress on the surfaces, assuring safety of use.

- The strength of tempered glass is approximately 5 times that of ordinary glass.

- When tempered glass is broken by external force, it forms small, bean-sized particles, reducing harm to humans.

- It can withstand rapid temperature changes (for example, 5mm tempered glass can withstand temperature changes up to 200 degrees Celsius).

- Tempered glass carries a risk of spontaneous breakage, so it should undergo a Heat Soak Test to ensure safer usage.

Heat Soak Test

To mitigate the occasional presence of nickel sulfide (NiS) impurities in tempered glass, which can undergo a phase change from high-temperature α-NiS to low-temperature β-NiS, causing a 2-4% volume expansion, strict control measures are employed in a controlled temperature soaking furnace. If these impurities are located within the tensile zone of the glass, they may undergo spontaneous fracture in the soaking furnace, reducing the risk of spontaneous breakage of tempered glass after installation.