Tempered Treatment Of Glassware

- Mar 27, 2018-

Tempered treatment: Glass products often rupture due to impact force exceeding the strength. The products that are processed by thermal tempering or chemical tempering are called tempered glass products, which are prestressed and have high impact strength. The hot tempering treatment is to uniformly heat the product to near the softening temperature, and rapidly cool the surface of the product with wind or oil quench to cause a huge temperature difference between the surface cooling and the central heat. There is no stress caused by the temperature difference above the strain temperature at the center of the product. When the product surface is cooled to room temperature, the center will also enter a rigid state. Continue cooling will produce the stress caused by the contraction effect. Finally, the temperature difference between the surface and the center disappears, and the surface compressive stress and the central tensile stress permanently exist. The chemical tempering treatment is to place the product in a hot potassium molten salt. The potassium ion with a large ionic radius is replaced by a sodium ion with a small ionic radius on the surface of the glass. The potassium ion replaces the sodium ion vacancy to cause the surface glass structure of the product to be squeezed and generate pressure. stress. The surface compressive stress of tempered glass products is significantly increased, and the impact strength against external forces is significantly increased. Two kinds of glass composite molding products with different surface and central components, due to different shrinkage after cooling, cause compressive stress on the surface of glass products, and such high-strength glassware is called sandwich glass products.