Calcined alumina micro powder SAL25S

Preparation, Characteristics, and Application of Calcined Alumina Micropowder SAL25S

Introduction

Aluminum oxide (Al ₂ O3) is an important inorganic material widely used in ceramics, refractory materials, catalysts, electronic devices, and other fields. Calcined alumina micro powder SAL25S is an alumina micro powder that has undergone high-temperature calcination treatment, and has excellent properties such as high purity, high hardness, high temperature resistance, and corrosion resistance. This article will provide a detailed introduction to the preparation process, physical and chemical properties, and applications of SAL25S in different fields.

1、 Preparation of calcined alumina micro powder SAL25S

1. Raw material selection

The preparation of calcined alumina micro powder SAL25S usually uses industrial grade aluminum hydroxide (Al (OH) ∝) or alumina hydrate as raw materials. The purity, particle size, and crystallinity of raw materials have a significant impact on the performance of the final product. High purity raw materials can reduce impurity content and improve the chemical stability of products.

2. Calcination process

Calcination is a crucial step in the preparation of SAL25S. During the calcination process, aluminum hydroxide or aluminum oxide hydrate undergoes dehydration reaction at high temperature to produce aluminum oxide. The calcination temperature, time, and atmosphere have a significant impact on the crystal structure, particle size, and specific surface area of the product.

-Calcination temperature: usually controlled between 1200 ℃ and 1500 ℃. Low temperature can lead to incomplete transformation of alumina crystal structure, while high temperature may cause particle sintering, affecting the dispersibility of micro powder.

-Calcination time: Calcination time is closely related to temperature, usually 2 to 6 hours. Extending the calcination time appropriately can promote crystal transformation, but prolonged time may lead to particle coarsening.

-Calcination atmosphere: Calcination is usually carried out in air or an inert atmosphere to avoid the introduction of impurities.

3. Crushing and Grading

The calcined alumina block needs to be crushed and graded to obtain the desired micro powder particle size. Common crushing equipment includes ball mills, air flow mills, etc. The grading process uses screening or airflow grading to remove particles that are too large or too small, ensuring uniform particle size distribution of the micro powder.

2、 Characteristics of calcined alumina micro powder SAL25S

1. Physical characteristics

-Particle size: The particle size of SAL25S is usually in the micrometer range, with an average particle size of 2-5 micrometers. Narrow particle size distribution is beneficial for improving the density and uniformity of materials.

-Specific surface area: The specific surface area of SAL25S is relatively low, usually between 1-5 m ²/g, indicating that its particle surface is smooth and has fewer internal pores.

-Density: The true density of SAL25S is close to the theoretical value (3.97 g/cm ³), indicating high crystallinity and dense structure.

2. Chemical characteristics

-Purity: The alumina content of SAL25S is usually higher than 99.5%, with extremely low impurity content, ensuring its chemical stability and corrosion resistance.

-Crystal form: After calcination, SAL25S is mainly in the α - Al ₂ O3 crystal form, which has high hardness and thermal stability.

3. Mechanical characteristics

-Hardness: The Mohs hardness of SAL25S is 9, second only to diamond, and it has excellent wear resistance and scratch resistance.

-Strength: SAL25S particles have high mechanical strength and can withstand significant pressure and impact.

3、 Application of calcined alumina micro powder SAL25S

1. Ceramic materials

SAL25S is widely used in the preparation of advanced ceramics, such as structural ceramics, electronic ceramics, and bioceramics. Its high purity and fine particle size contribute to improving the density and mechanical properties of ceramics.

2. Refractory materials

SAL25S is an important raw material for preparing high-performance refractory materials, such as refractory bricks, refractory castables, etc. Its high temperature resistance and corrosion resistance ensure the stability of refractory materials in extreme environments.

3. Catalyst carrier

The high specific surface area and chemical stability of SAL25S make it an ideal catalyst carrier, widely used in fields such as petrochemicals and environmental protection.

4. Electronic components

SAL25S is used for the preparation of electronic ceramics, insulation materials, and semiconductor devices. Its high purity and excellent thermal conductivity help improve the performance and reliability of electronic devices.

5. Abrasives and polishing materials

The high hardness and wear resistance of SAL25S make it an ideal material for manufacturing abrasives, polishing powders, and grinding media, widely used in metal processing, glass polishing, and precision device processing.

4、 Conclusion

Calcined alumina micro powder SAL25S has high purity, fine particle size, high hardness, and excellent chemical stability through precise preparation process and strict quality control. Its wide application in the fields of ceramics, refractory materials, catalysts, electronic devices, and abrasives demonstrates its enormous potential as a high-performance material. With the continuous advancement of technology, the application prospects of SAL25S will become even broader, providing strong support for the development of various industries.