What is Alumina Micropowder WCA?

The platelet alumina micropowder WCA is well-known for its unique platelet structure. Initially, platelet alumina micropowder was developed by Microgrit in the United States. Researchers discovered that alumina crystals that have undergone high-temperature calcination under certain conditions have a hexagonal platelet crystal shape. If used for grinding, this structure will not have many sharp corners like traditional alumina. That is conducive to the grinding of fine components. WCA micropowder is the specification name of Microgrit company. Since then, Japanese semiconductor material giant FUJIMI has also produced a similar product, spec name PWA. Therefore,  alumina micropowder WCA and PWA are the same form of alumina powder.

production principle

The production principle of plate shape alumina micropowder is as follows: Adding molten salt material in the high-temperature calcination process. On the one hand, the migration rate of alumina in the molten salt is much higher than that of conventional solid-state reactions.  It can reduce the reaction temperature and shorten the reaction time for synthesizing α – Al2O3. On the other hand, due to the different wetting degree of the molten salt on each crystal surface, there are differences in the surface energy of each crystal surface. That results in different crystal growth rates and ultimately the formation of flakes. Currently, platelet alumina micropowder manufacturer from China mainly use the method of high-temperature calcination of molten salt for production.

The platelet aluminum oxide micro powder produced by high-temperature calcination of molten salt has a content of aluminum oxide equivalent to that of electric fused aluminum oxide micro powder. The alumina content is more than 99%. The crystal is in a hexahedral flat shape, and the thickness of a single crystal is about 2-3um. After calcination, the alumina aggregate needs to be ground and graded to obtain powders of different particle sizes. The particle range is usually between 3-50um, mainly used for grinding and polishing semiconductor silicon wafers and optical crystals.

Advantages

The advantages of platelet alumina micropowder include avoiding scratches during flat sliding grinding, strong grinding force, high grinding efficiency, and easy dispersion without agglomeration.