Brown Fused Aluminum Oxide Sandblasting Abrasive UK

In the process of this movement, the small droplets first form a small ball under the action of surface tension and centrifugal force(aluminum oxide abrasive). When the small ball is cooled suddenly, the surface solidifies instantly, but the inside of the ball is still in the liquid state. Alumina in high temperature liquid state has higher thermal expansion rate(glass bead abrasive). The linear expansion coefficient of high temperature liquid is three times of that of solid state.

Brown Fused Aluminum Oxide Sandblasting Abrasive UK MOQ: 1 Ton! 19 Years Experience Brown Fused Aluminum Oxide Manufacturer, 35,000m² Workshop Area, Free Samples, Fast Delivery!

If you want to buy brown fused aluminum oxide sandblasting abrasive, please click our products: Brown Fused Aluminum Oxide for more information!

Under the action of centrifugal force(aluminum oxide grit), at the same time, the molten liquid shrinks greatly, which makes the molten liquid condense on the shell of the hollow ball quickly and evenly, and completes the whole process of forming the hollow ball. When the chemical bond such as ion bond component in the molecule is larger, the volume difference between the melt and the solid is larger(aluminium oxide sandblasting). Otherwise, the larger the covalent bond component is, the smaller the volume difference is.

(brown fused aluminum oxide sandblasting abrasive uk)For example, alumina begins to volatilize above 1750 ℃, and the volatilization increases above 2300 ℃(brown fused alumina). Although the linear expansion of alumina is only 1.6% - 1.8% when heated to 1800 ℃, when the oxide is heated to the melting point temperature, when the substance changes from solid phase to liquid phase, and some of them can not be removed, the volume expansion will be 20% - 40%(steel shot abrasive). This volume expansion is related to the chemical bond of the molecule.

When alumina is transformed from solid phase to liquid phase, its molar volume expands about 23.5%(brown aluminum oxide). Therefore, thermal expansion and cold shrinkage are the basic reasons for the formation of alumina hollow spheres. This is the same reason that shrinkage cavity is easy to be produced in the production of fused cast bricks(glass beads manufacturers). The temperature of alumina melt fluctuates between 2200-2300 ℃ when the alumina hollow ball is blown.(brown fused aluminum oxide sandblasting abrasive uk)

Because of its strong hygroscopicity, there is a certain gas partial pressure in the high temperature liquid(brown aluminium oxide). This partial pressure accelerates the expansion of the high temperature liquid, which is an important factor to promote the formation of alumina hollow spheres. A large number of honeycomb like pores can be seen in the fused corundum. The apparent porosity of 3-5mm is about 10% ~ 15%(80 grit aluminum oxide). Therefore, it can be concluded that there is a large gas partial pressure in the melt.

(brown fused aluminum oxide sandblasting abrasive uk)There are two main aspects of the gas partial pressure in the formation of high-temperature molten liquid(white alumina): first, in the process of electric melting, when the powdered industrial alumina is added, part of the air brought in during the operation is still left in the high-temperature molten liquid after the electric melting(garnet abrasive price); Secondly, in the process of electrofusion, all kinds of oxides, especially low melting point oxides, gradually increase the evaporation rate.

In the process of electrofusion, 30% ~ 40% of silicon dioxide impurities in industrial alumina will be volatilized, and other impurities with low melting point(silicon carbide price), such as potassium, sodium and other oxides, will be volatilized in a larger proportion. These gases are limited by the poor fluidity of high temperature molten liquid(220 grit aluminum oxide), so that the gas partial pressure inside the molten liquid increases, and the honeycomb like pores are formed during the cooling process.