Introduction of Black Corundum Practical Application

The English name of black corundum is black fused alumina, black aluminium oxide, black synthetic corundum and so on.

It is a kind of gray-black crystal with Al₂O₃ and iron spinel as the main ore phase, which is made of high alumina bauxite plus high iron bauxite or iron oxide chips, and then melted and smelted at high temperature in an electric arc furnace. Its main chemical composition is aluminum oxide (Al2O₃), iron oxide (Fe2O₃), and some silica (SiO₂), titanium dioxide (TiO₂) and other ingredients. The black corundum production process determines that the power consumption is lower than that of brown corundum, with less emissions, and is an environmentally friendly and cost-effective abrasive product.

Black corundum abrasive is traditionally mainly used for surface blasting, grinding, polishing and other surface treatments of various workpieces, especially for stainless steel workpiece polishing. It has a unique advantage. Black alumina is mainly used for grinding and polishing alumina particles from the microstructure. The microcrystalline state is scattered, and the surrounding is surrounded by a slightly lower strength silicon oxide, similar to the structure of piled abrasive. It has the advantages of moderate softness and hardness, good self-sharpness, low grinding heat generated during grinding and polishing, and difficult to burn the surface of the workpiece. The surface of the stainless steel workpiece polished by black alumina is uniform and consistent, showing the inherent luster of stainless steel, and there will be no burn marks.

In the past ten years, research on the application of black corundum has been gradually deepened and applied more widely. It is found that black corundum is compounded with other abrasives with high hardness and durability. Surface treatment.

At present, the polishing and grinding effects of black corundum are mainly divided into two categories:

First, black corundum grain sand # 100 is finely used for sand blasting, grinding and polishing of various stainless steel, ordinary steel, copper, aluminum, bamboo, glass and other workpieces, especially on the stainless steel surface. . Polishing stainless steel workpieces with black corundum is not easy to burn the surface of the workpiece. After polishing, the surface of the workpiece shows a bright and uniform color of stainless steel itself, and its appearance is very high. Unlike brown corundum, white corundum, etc., it is easy to burn the workpiece after throwing, and the phenomenon of dark hair and dark color difference in some parts is prone to affect the visual effect of the product.

Taking stainless steel workpiece polishing as an example, the following describes the specific use of black corundum. Traditionally, first put several cloth wheels on the shaft of the polishing machine, then apply the boiled bone glue to the outer circle of the cloth wheel, and then place the outer circle with the bone glue coated cloth wheel on the sand plate with black corundum. After rolling inside, after the outer circle of the cloth wheel is evenly bonded with the black corundum sand, put the cloth wheel into the oven until the bone cement is solidified, the black corundum sand is firmly bonded to the cloth wheel, and the cloth wheel can be taken out and mounted on the polishing machine The polishing machine rotates, and the workpiece to be polished contacts the outer circle of the cloth wheel with an appropriate force, and the workpiece can be polished.

It can also be made from black corundum into abrasive cloth and converted into abrasive belt, and made into sponge blocks, resin abrasive wheels, nylon wheels and other abrasive products for polishing.

The second is the need to grind and polish the workpiece. When there is a certain grinding requirement, black corundum can also be compounded with other abrasives with higher hardness and better wear resistance to make polishing wheels, fiber wheels, abrasive belts, etc. Abrasive products are more effective than polished products made of black corundum or other abrasives, and have better grinding and polishing effects and higher cost performance.

The key point to pay attention to is: use black corundum polishing, especially stainless steel surface polishing treatment, use pure black corundum abrasive; if it is polishing, if it needs grinding, it can work with other brown corundum, Calcined brown corundum, single crystal corundum, silicon carbide, etc. have better composite effects and higher cost performance!

It is believed that the technical staff of various abrasive product manufacturers will be able to use pure black corundum for surface polishing according to the characteristics of black corundum. When grinding is required, they will be compounded with the original abrasive to produce better performance and more cost-effective High abrasive products. It will definitely enable black alumina to play a greater role in the field of polishing and grinding, to improve product performance and improve cost performance.