The Application of the Alumina Powder and the Processing Equipment

Alumina powder is a raw material usually made of industrial aluminum hydroxide or aluminum oxide. As a white amorphous powder that is difficult to dissolve in water, it is suitable for surface beautification or coating on various high-end items, crafts, or hardware products. After sandblasting or coating, the surface gets white and free of any impurities, eliminating the trouble of cleaning. The production process of alumina powder is getting higher and higher, and alumina powder below 1 micron can be produced. So what are the characteristics and applications of such fine alumina powder?

First, the function of aluminum oxide powder in the ceramic manufacturing process. Alumina powder, similar to brown corundum, can be divided into calcined or ordinary industrial alumina when used as ceramics. Calcined alumina is an essential raw material for antique tiles production, while industrial alumina can be used to produce microcrystalline stone. In traditional glazes, alumina is often used as a raw material for whitening. As antique tiles and microcrystalline stones are favored by the market, the amount of alumina also increases yearly.

Second, alumina is often used in glass-strengthening production, thanks to its high corrosion resistance. It also makes metal aluminum stand with corrosion in the air. Pure metal aluminum easily reacting with oxygen in the air, forms a thin alumina layer film covering the surface exposed to the air.

Third, alumina has high thermal conductivity. Compared with crystalline silicon powder, alumina powder can be filled with high density to obtain a mixture with high thermal conductivity and good heat dissipation. It is not only the basic raw material for manufacturing metal aluminum, but also used to make various refractory bricks, refractory crucibles and tubes, and high-temperature-resistant experimental instruments. Besides, it is widely applied as abrasives, flame retardants, fillers, etc. The high-purity α-type alumina is the raw material for producing corundum, ruby, and sapphire artificial. The production of the substrate in modern large-scale integrated circuits also uses alumina powder.

Of course, the other characteristics of the alumina powder, such as low wear resistance and high filling, are widely applied. Aluminum powder processing and manufacturing usually requires grinders (bead mills). Bead mills, the wet ultrafine grinding equipment, are developed from ball mills, commonly used to disperse and grind nano new material powders, electronic ceramics, ceramic inks, pigments in the paint, inks, and so on.

Compared with other grinding equipment such as ball mills, roller mills, and colloid mills, bead mills have the advantages of high production efficiency, strong continuity, low cost, and high particle fineness. The fineness output from bead mills is adjustable by adding or removing grinding media, adapted to various processes. The bead mill overcomes shortcomings such as poor particle size distribution from grinding by the traditional type.