Tempered glass tempered glass is obtained by cutting ordinary annealed glass into required dimensions, then heating it to approximately 700 degrees near the softening point, and then obtaining rapid and uniform cooling (usually 5-6 mm of glass is heated at 700 degrees for 240 seconds. About 150 seconds cool down. 8-10MM glass is heated at about 700 degrees for about 500 seconds and cooled for about 300 seconds. In short, depending on the thickness of the glass, the time for heating and cooling is different.) After the tempering treatment, uniform compressive stress is formed on the surface of the glass, and tensile stress is formed on the inside of the glass. This increases the bending strength and impact strength of the glass, and its strength is approximately four times greater than that of ordinary annealed glass.