Whether bulk density can reflect granularity and particle type of silicon carbide powder

The packing density is an important technical parameter of carbide silicon powder. It means the micronized powder flows into the container in specific ways and means. The ratio between quality and volume can be expressed in g/cm3.

Compared with coarse particles of abrasive bulk density measurement methods, measurement of differential packing density are much more complex, because the micronized particle diameter is relatively small, the adhesive force between the particles, friction and particle weight at an order of magnitude, particle each adsorption, the formation of agglomeration. The smaller the particle diameter, the agglomeration of the more serious. Measure the bulk density of silicon carbide powder particles must be dispersed, it is necessary to exert a certain force, when the external force is greater than the adhesive force and friction between the micronized particles, micronized particles will separate, external forces generated by a variety of ways to achieve the mechanical vibration.

The particle shape is posed by the various points on the outline of a particle boundary image. An important feature of the shape of the particles of silicon carbide powder, silicon carbide powder, and micronized particle shape directly affects the mobility of the silicon carbide, the packing density, surface oxidation. Observation and study of particle shape and surface structure can be observed by optical microscopy, electron transmission microscopy and scanning electron microscopy, the thick silicon carbide powder with a magnifying glass or the naked eye.

Micronized particles have a variety of shapes. They can not have assertion that which is the most suitable shape. Even if the same powder production way will produce different particle shape, the main purpose of multi-line cutting of silicon carbide powder angular irregular, diamond is the best and worst blunt shape.

All kinds of powder bulk density are reduced with the reduction of particle size when particle size is reduced to a certain extent, the packing density will be less than 000 g / cm3. This is because the gap between the particles increases as the particle size decreases, the micronized particles increase the surface area. Under normal circumstances, the micro powder bulk density is greater than the packing density of green silicon carbide powder, the packing density of green silicon carbide powder is greater than the packing density of black silicon carbide powder.

Sharp silicon carbide powder for the same model than the blunt silicon carbide powder particle diameter of the large gap between the sharp particles, so that the packing density of smaller; between the different models, the packing density decreases with the reduction of particle diameter This is because the gap between the particles increases as the particle size decreases, the micronized particles increase the surface area.

Different packing densities of raw material metal powder have significant difference. In the same raw materials and particle size, packing density of green silicon carbide powder can discriminate the grain type of micronized powder. In different particle size case, with the particle diameter becomes smaller, the packing density of green silicon carbide powder gradually decreases. When the particle diameter is reduced to a certain extent, the bulk density is less than 1.000 g / cm3.

Source:http://www.mhcmp.com