Now the glass manufacturer’s technology is getting better and better, producing a better material of glass, glass structure is also diversified, but occasionally found that some factories produced a small amount of glass bubbles, why these bubbles will occur, what causes the emergence of these bubbles, the following together to learn. The gas in the gap of raw material particles and the gas adsorption on the surface of the raw material, in the early stage of the fusion of the material, this kind of gas will continue to evaporate or evaporate, in the process of rising to form a large bubble floating on the glass liquid, generally does not directly lead to visible bubbles in glass products.
Unless the particle size of the raw material is not properly controlled, the combined material mass does not melt sufficiently, the gas can not be discharged. Salt decomposition released gas, the material has a large number of carbonates, sulfates and nitrates, these salts are thermaldecomposition, produce a large number of tiny bubbles, due to the salt decomposition of the amount of gas produced, about 15-20% of the weight of the material, compared with the formation of glass liquid, the volume is many times larger.
The massive release and continuous movement of these gases promote the efficiency of heat exchange, accelerate the melting of the material, improve the uniformity of the glass composition and temperature uniformity, but the formation of such gases will not be eliminated in a timely manner will form glass bubbles. What are the sources of gas in glass bubbles? Gas produced by external factors. Refractory materials to extract gas, harmful impurities components and glass liquid action produced by the gas, these gases formed glass bubbles in normal production disappeared for a long time, disappear ingesty, but this situation is relatively rare. Glass liquid cooling too fast or temperature fluctuations, or for various reasons, the redox state of the glass has a large fluctuation, these factors combined, so that the solubility of various gases in the glass liquid fluctuates, releasing a large number of tiny secondary bubbles.
This bubble is characterized by a small diameter and a large number. Sometimes due to the calculation error of the material or the addition error in the process of material execution, the glass composition in the pool kiln fluctuates greatly, the solubility of the gas in the glass fluctuates, and a large number of glass bubbles are produced. There are two ways in which glass bubbles eventually disappear during the clarification process: one is that small bubbles grow and become large bubbles, which disappear as density differential bubbles continue to float and eventually escape from the glass liquid. The other is a tiny bubble, with the temperature decrease, the solubility of the gas in the glass increases, due to the surface tension, the bubble has several components of the gas, because the bubble diameter is small, the pressure is high, the gas is quickly absorbed by the glass, with the diameter becomes smaller, the bubble pressure increases, the final bubble in the gas all dissolved into the glass.
The small bubbles disappear completely. After the glass bubbles, it affects the beauty of the glass structure. Through the above article I believe that you already know why bubbles appear in the glass production process.