Low Soda Calcined Alumina Powder 70um
Calcined Alpha Alumina
Calcined alpha alumina is made by calcining a source alumina powder at 1200-1300C to convert it to pure Al2O3. This is the densest and most stable crystalline form of alumina. It is insoluble in water but is soluble in hydrofluoric acid and potassium bisulfate. When nearly 100% of the material converts to the large hexagonal, elongated tablet shaped crystals associated with the alpha phase, the product is referred to as "Tabular Alumina". Unground calcined aluminas are typically 100-300 mesh, but much finer grades (often called "Ground Alumina") are produced by milling. Calcined aluminas are available in numerous grades based on the heat treatment applied, crystal size, soda content, and degree of thermal conversion to alpha phase. Soda content is a major factor in determining the final use (low soda materials are used for electronic applications, medium soda for electrical insulation and porcelains, high soda for glass, glaze, fiberglass and electrical porcelain).
This product is a white powder crystallized by high temperature calcination, the average particle size is 70um, the product has the characteristics of coarse powder, less dust, good fluidity, insoluble in water, easy to grind and so on, a-alumina with a high melting point, good thermal stability, low impurity content, strict particle size control. Therefore, it is widely used in the fields of isostatic pressing and dry pressing, slip casting, extrusion molding and injection moulding.
Brand | GF-71 | AF-82 | GP-71 | AP-82 | AL-82 | A-71 | A-82 | AB-71 | |
Phase | Phase | Semi-quantitative（%） | |||||||
a-Al2O3 | 96 | 96 | 96 | 97 | 96 | 95 | 96 | 93 | |
Primary Crystal size um | 3-5 | 3-5 | 3-5 | 3-5 | 1-1.5 | 2-4 | 2.5-3.5 | 0.5-1.5 | |
Chemical content | Content | Content（%） | |||||||
L.O.I. 1025o | 0.05 | 0.03 | 0.05 | 0.03 | 0.06 | 0.07 | 0.06 | 0.1 | |
Al2O3 | 99.8 | 99.8 | 99.8 | 99.8 | 99.8 | 99.5 | 99.5 | 99.5 | |
SiO2 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | 0.03 | |
Fe2O3 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | 0.02 | |
CaO | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | |
MgO | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | |
K2O | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | |
Na2O | 0.05 | 0.02 | 0.08 | 0.06 | 0.06 | 0.35 | 0.35 | 0.35 | |
TiO2 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | 0.01 | |
Calcined whiteness | Condition | Result | |||||||
1200o 30 Min | 97 | 97.8 | 97 | 97.6 | 97 | 97 | 98 | 98.4 | |
This product is mainly used in the production of castables and refractory materials, high quality ceramic components for spark plugs, insulators, electronic substrates, wear-resistant ceramics and functional ceramics and other fields.
