White corundum uses industrial alumina powder as the production raw material. It is made by melting at a high temperature above 2000 degrees in an electric arc, cooling, crushing and shaping, magnetic separation to remove iron, screening, packaging and other processes. Pointed, suitable for the manufacture of ceramics, resin bonded abrasives, grinding, polishing, sandblasting, precision casting, manufacturing refractory materials and other fields. Most of the white corundum produced now is for export.
White corundum ceramic abrasives are one of the important uses of white corundum abrasives. The production process of white corundum ceramic abrasives is complicated and the firing temperature is high, so the cost of the manufactured products is relatively high, but many of the manufactured abrasives appear Different degrees of yellowing phenomenon directly affect the requirements of commercialization of ceramic abrasive tools.
The reason for the yellowing of the white corundum ceramic
grinding tool The spectral composition of the light reflected on the surface of the white corundum ceramic grinding tool determines the color that people know about it. If the surface of the white corundum ceramic grinding tool can reflect all the light that shines on it is pure white. Many factors, especially the mineral composition and content of clay raw materials, affect the whiteness of ceramic abrasive tools. Fe2O3, FeO, TiO2, MnO2 and other oxides in the blank will reduce the whiteness of white corundum ceramics.
Because the raw materials used in white corundum ceramic abrasive tools, especially the clay itself, contain a certain amount of iron and titanium impurities, and white corundum abrasives will also introduce some iron during mechanical processing, which makes ceramic abrasive products fired in an oxidizing atmosphere. , The iron and titanium oxide impurities in the green body form a color center coloring phenomenon, which makes the white corundum ceramic products yellow. That is to say, the existence of iron and titanium ions is the root cause of the yellowing of white corundum ceramic abrasive tools.
The way to whiten the white corundum ceramic grinding tool
(1) Carry out magnetic separation on the raw material white corundum abrasive, and remove part of the ferromagnetic substances in the white corundum through the action of a strong magnetic field, so as to reduce the content of ferromagnetic substances to achieve white corundum ceramic grinding. (2) Change the firing atmosphere of white corundum ceramics, change the oxidizing atmosphere to reducing atmosphere so that free iron ions exist in the form of divalent iron ions, so that the white corundum products appear light blue, so that
To achieve the whitening effect of white corundum ceramic abrasive tools;