High borosilicate glass is a low expansion rate, high temperature, high strength, high transmittance and high chemical stability of special glass materials. High-borosilicate heat-resistant glass, instantaneous temperature difference -20 ℃ -150 ℃, boiling water to 100 ℃, because of the special heat-resistant glass material, the glassware placed in the refrigerator 12 hours after boiling directly into the boiling water are no problem, which It is also one of the reasons why it is used as an experimental apparatus.
(1) With correctness and stability, the chemical composition, moisture and particle size of various raw materials in the compounding material should be kept relatively stable so as to ensure the correctness and stability of the molten glass components
(2) a certain amount of water (5%), water plays a beneficial role in the evenness of the mixture, dry materials are not easy to mix and easy stratification on the unfavorable melt. Raw material particle size changes with the amount of water added to the compound also changes, the more water particles should be more
(3) a certain gas rate, in order to make the glass easy to clarify and homogenization, the compound must contain some of the raw materials can break down the gas such as boric acid, aluminum hydroxide, sodium nitrate and other gases out of the amount and weight of the compound Than the gas ratio. Borosilicate glass gas rate is generally 9 to 15%.
(4) with uniform (≥ 95%), with the expected physical properties should be: uniform