Tempered Glass (Heat-Strengthened Glass) is produced by heating annealed glass to its softening point and then rapidly cooling it under carefully controlled conditions. This thermal treatment creates a permanent surface compressive stress layer, significantly increasing the glass's mechanical strength, impact resistance, and thermal shock resistance compared with ordinary annealed glass.
Features：
Enhanced Safety – When broken, the glass fractures into small, blunt-edged granules, significantly reducing the risk of serious injury compared with ordinary glass.
High Strength – Tempered glass offers 3–4 times the mechanical strength of ordinary annealed glass, providing excellent resistance to impact and bending.
Excellent Thermal Stability – Tempered glass can withstand temperature differences of up to 200°C without breakage, making it suitable for demanding architectural and industrial applications.

Heat-Strengthened Glass differs from fully tempered glass in its surface compressive stress level and offers excellent thermal stability. Due to its lower surface stress, it does not exhibit the same breakage characteristics as tempered safety glass. Under current Chinese safety glazing regulations, heat-strengthened glass is not classified as safety glass.

Curved Tempered Glass and Curved Heat-Strengthened Glass are manufactured by heating annealed glass to its softening point, bending it to the required curvature, and then rapidly cooling it with a precisely controlled air-quenching process. This process produces glass with a permanent curved profile and enhanced mechanical strength, thermal stability, and optical quality.

Heat-Soaked Tempered Glass (also known as Heat Soak Tested Tempered Glass) is soda-lime-silicate tempered glass that undergoes an additional heat soak treatment under controlled process conditions. During the treatment, the tempered glass is placed in a heat soak furnace and subjected to a controlled cycle of heating, soaking, and cooling. This process promotes the phase transformation of nickel sulfide (NiS) inclusions, significantly reducing the risk of spontaneous breakage in service.

GB 15763.2 – Safety Glazing Materials in Building – Part 2: Tempered Glass (Chinese National Standard)

GB/T 17841 – Heat-Strengthened Glass (Chinese National Standard)

GB 17841 – Tempered and Heat-Strengthened Glass for Curtain Walls (Chinese National Standard)

ASTM C1048 – Standard Specification for Heat-Treated Flat Glass (USA)

BS EN 12150 – Thermally Toughened Soda Lime Silicate Safety Glass (European Standard)

BS EN 1863 – Heat-Strengthened Soda Lime Silicate Glass (European Standard)

AS/NZS 2208 – Safety Glazing Materials in Buildings (Australia/New Zealand Standard)

GB 15763.4 – Safety Glazing Materials in Building – Part 4: Heat-Soaked Tempered Glass (Chinese National Standard)

BS EN 14179-1 – Heat Soak Tested Thermally Toughened Soda Lime Silicate Safety Glass (European Standard)