The Secret Of Alumina Ceramic Granulation Powder.
In order to improve the fluidity of alumina powder granulation, improve the sintering performance, and reduce the sintering temperature, it is necessary to make the alumina powder into false particles, that is, granulated powder.
Therefore, the model is filled uniformly, so as to improve the molding density of the green body and ensure the sintering density after the porcelain is formed. In the production process of alumina ceramic products, granulation is one of the most basic and important links.
The 92% and 95% alumina granulation powder produced by Shandong Avant mainly adopts the production process of spray granulation. The granulation tower is atomized, and spherical particles with better fluidity can be obtained. The output of spray granulation is large and suitable for industrial mass production.
In the production of Shandong Avant, spray granulation avoids the re-agglomeration or sedimentation of each component in the slurry, so that the slurry is kept uniform; at the same time, the slurry is uniformly atomized, and spherical particles with uniform particle size distribution and good fluidity can be obtained.
Such particles have excellent forming and sintering properties, which help to finally obtain a sintered body with high density and high flexural strength.
The shape of the granulated powder will directly affect the fluidity and bulk density of the product. Changes in fluidity and bulk density will cause | changes in the compacted density of the green body, which in turn affects the changes in the firing density and shrinkage of ceramics.
Therefore, how to ensure that the granulated powder has a good particle shape is a problem that must be solved in the production process.
The most fluid particle shape should be spherical. However, in the production process, due to various reasons, the granulated powder often forms a non-spherical shape. The typical shapes of granulated powder particles are as follows:
(1) Medium-solid type: spherical: it is the best shape; apple-shaped with a shallow pit on the ball is not as ideal as a spherical shape, but it is still a good shape in large-scale industrial production.
(2)Broken type: The particles are in the form of broken lumps.
(3) Bonding type: In the light case, one or more small particles are adhered around a large particle, and in the heavier case, many particles of different sizes stick together into a group.
(4) Hollow type: depending on the degree, there is a hollow shape with a deep pit on the sphere; there is a bead shape with a through hole in the middle.
