Pink alumina, commonly known as pink fused alumina (PFA), is a popular synthetic material known for its hardness and durability. This material is widely used in various applications such as sandblasting, grinding, grinding and more.
Pink alumina parameters
Hardness: Approximately 9 on the Mohs scale.
Grit Size: Varies from coarse (12-24 grit) for aggressive material removal to fine (80-220 grit) for precision applications.
Density: Approximately 3.96 g/cm3, heavier than many other abrasives.
Melting point: above 2000°C, able to withstand extremely high temperatures.
Crystal Structure: Triangular crystal structure, which contributes to its hardness and durability.
Chemical stability: Resistant to most acids and alkalis, suitable for use in a variety of chemical environments.
Manufacturing process of pink alumina
The production of pink alumina involves melting calcined alumina and chromium oxide at high temperatures in an electric arc furnace. The process produces a material that is tougher and harder than white alumina.
1. Calcined Alumina: Alumina is derived from bauxite and is calcined at temperatures above 1000°C to eliminate impurities and moisture.
2. Fusion with chromium oxide: The calcined alumina is then mixed with chromium oxide and subjected to intense heat in an electric arc furnace. This results in the formation of pink aluminum oxide.
3. Cooling and pulverizing: The molten pink alumina is cooled and then pulverized into the required particle size. The crushed material is then screened to ensure quality.
Applications of pink alumina
Pink alumina has high hardness and toughness and is widely used in various industries. Here are some key applications:
Sandblasting: The hardness and sharpness of pink aluminum oxide make it very effective in sandblasting applications for surface preparation, cleaning and etching. Its toughness allows it to be reused multiple times, making it a cost-effective option.
Grinding Wheels: The material's hardness and durability make it an excellent choice for making grinding wheels and other abrasive tools. They are used for cutting, grinding and polishing metal and other hard materials.
Grinding and Polishing: The fine grain size of pink alumina is particularly suitable for precision grinding and polishing applications. They are used in industries such as electronics and optics to help achieve smooth and precise surfaces on a variety of materials.
Refractories and Ceramics: Due to its high melting point and thermal stability, pink alumina is used to make refractory materials that can withstand extremely high temperatures without losing their strength or shape. It is also used in the ceramic industry for similar reasons.
Coated Abrasives: Pink aluminum oxide is used as the abrasive grain in many coated abrasives, such as sandpaper and sanding belts. Its hardness allows it to perform sanding and finishing operations efficiently.
Anti-Slip Applications: In some cases, pink aluminum oxide can also be used in anti-skid applications due to its hardness and wear resistance. It can be added to surfaces to increase traction and prevent slipping.
Please note that the specific uses of pink alumina depend on its specific parameters, such as grain size and hardness. Different applications may require different specifications of pink alumina.
Compare Aluminum Oxide: White, Brown, Black and Pink
There are many types of aluminum oxide, each with unique properties suitable for different applications. The most common types are white, brown, black and pink aluminum oxide. This section compares and contrasts these materials.
1.White alumina
White Aluminum Oxide (WA) is a high-purity synthetic abrasive made from reducing fusion of high-quality aluminum oxide powder. It is characterized by self-sharpening and high cutting force. The hardness of WA is slightly higher than that of brown corundum, but its toughness is lower.
Hardness: high, slightly higher than brown corundum.
Toughness: lower than brown alumina.
Applications: Precision grinding, surface finishing and cutting tools.
2. Brown alumina
Brown alumina (BA), commonly known as fused alumina, is produced by reducing bauxite in an electric arc furnace. It is a hard and tough material used in the manufacture of grinding wheels (ceramic grinding wheels and resin grinding wheels) and coated products.
Hardness: high, slightly lower than white corundum.
Toughness: high, higher than white corundum.
Applications: Resin bonded and vitrified bonded grinding wheels, blasting media, metal preparation.
3. Black aluminum oxide
Black aluminum oxide is a durable, sharp abrasive with a lower Al2O3 content than brown and white aluminum oxide. It has lower purity and higher toughness, making it ideal for some rougher applications.
Hardness: High, but usually lower than brown and white alumina.
Toughness: high, higher than white corundum and equivalent to brown corundum.
Applications: Sand blasting, flooring and anti-skid applications and rock tumbling.
4. Pink alumina
As mentioned earlier, pink alumina (PFA) is produced by fusing calcined alumina and chromium oxide. It is known for its superior hardness and durability, surpassing that of white aluminum oxide. Its high toughness is due to the presence of chromium oxide.
Hardness: Extremely high, exceeding white, brown and black alumina.
Toughness: High due to the presence of chromium oxide.
Applications: Sand blasting, grinding wheels, grinding and polishing.
In summary, each type of alumina has its own unique properties and applications. White and pink alumina are known for their high hardness, while brown and black alumina are known for their high toughness. Choosing the right type of alumina depends largely on the specific requirements of the application.
