I. General introduction
Brown corundum is a material composed of polycrystals or single crystals of α-Al2O3 crystal system. It is widely used in machinery manufacturing, mining, building materials and other fields due to its high hardness, good wear resistance and strong impact resistance. How to evaluate the quality of brown corundum? The following are the quality standards of brown corundum.
II. Physical performance standards
1. Hardness: The hardness of brown corundum is mainly determined by its main component α-Al2O3 and its crystal structure. The hardness is generally above 9.0.
2. Density: It is divided into ordinary brown corundum and high-density brown corundum. The density of ordinary brown corundum is 3.8~3.95g/cm3, and the density of high-density brown corundum is 4.0~4.05g/cm3.
3. Burning rate: The weight loss rate of brown corundum powder when heated to 1450℃ in air.
4. Flexural strength: The flexural strength of the material under specified conditions is generally above 500MPa.
5. Wear rate: The mass loss rate of the material surface in the wear test under specified conditions.
III. Chemical index standards
1. Chemical composition (main elements): Al2O3, Cr2O3, SiO2, Fe2O3, TiO2, etc.
2. Impurity elements: The content of CaO, MgO, Na2O, K2O, etc. should be within a certain range.
3. Moisture content: The moisture content in brown corundum powder should be below 0.2%.
