Components and features of cerium oxide polishing powder
The main ingredient of the cerium oxide polishing powder is cerium dioxide (CeO2), followed by lanthanum oxide (La2O3), praseodymium oxide (Pr2O3), also containing a trace amount of silicon oxide, aluminum oxide and calcium oxide. cerium oxide powder is widely used in glass polishing, which has strong cutting, short polishing time, long life, high precision polishing advantages. According to the content of the cerium oxide, cerium oxide polishing powder is divided into low cerium, medium cerium, high cerium polishing powder, their cutting forces and service life are from low to high.
Cerium oxide polishing powder effects in the polishing process
Cerium oxide polishing glass is a chemical-mechanical process. Cerium oxide polishing powder has two effects in the polishing process, namely mechanical action, and colloid chemistry, these two effects occur simultaneously. The initial stage of the polishing is the process for CeO2 to remove surface irregularities layer, and thus showing a new polished surface, the mechanical action is a major at this time. Meanwhile, since there is water in the polishing mixture, H3O ions are formed in the polishing process, H3O ion and Na ion mutually exchange in the glass surface and form hydrolysis compound with the glass; Furthermore, since CeO2 polishing agent has a polyvalent nature, the oxidation-reduction reaction of Ce (3) / Ce (5) will destroy the silicate crystal lattice, and oxidized the contact material from the glass surface with polishing agent, and forming a complex to be removed by chemical adsorption (including glass and hydrolyzing compound).
There are several theories on the interpretation of the cerium oxide polishing mechanism:
1. Chemical theory, the polishing process is a result of the chemical interaction among water, the polishing agent, polish mold material and glass.
2. Purely mechanical action doctrine, polishing is the continuance of grinding process.
3. Rheology doctrine, i.e. Friction heat makes the glass surface to produce the plastic deformation and flow, or heat-softened resulting in melting flow, the polishing process is the process the molecules on glass surface re-distributed and form a flat surface;
4. Mechanical, physical and chemical theory, the polishing process is a mechanical, physical and chemical effects process.
Experts believe that polishing is a mechanical, physical, chemical synthesis, wherein the mechanical action is basic, and the chemical action is important, while the rheology phenomenon exists. The reason why the cerium oxide is extremely effective polishing compound is because it can simultaneously polish glass with chemical decomposition and mechanical friction two forms. In the polishing process, cerium oxide producer has two effects, namely mechanical action and colloid chemistry action, these two effects occur simultaneously.
www.rareearth-china.com is committed to the production,research and development, sales ceramic raw materials and cerium oxides and other rare earthe materials for chemical industry, as well as chemical raw materials for glass-ceramic.
没有评论:
发表评论