Calcined alumina micro powder SAL30

Calcined alumina micro powder SAL30: characteristics, preparation and application

Introduction

Calcined alumina micro powder SAL30 is a high-performance inorganic material widely used in ceramics, refractory materials, electronics industry, catalyst carriers and other fields. Its unique physical and chemical properties, such as high hardness, high melting point, excellent wear resistance, and chemical stability, make it an indispensable material in many industrial applications. This article will provide a detailed introduction to the characteristics, preparation process, and applications of SAL30 in different fields.

1、 Basic characteristics of SAL30

1. Chemical composition

The main component of SAL30 is alpha alumina (α - Al ₂ O3), with a purity typically above 99.5%. Its crystal structure is hexagonal close packed, with excellent stability and mechanical properties.

2. Physical properties

-Particle size distribution: The particle size of SAL30 is usually between 0.5-3 microns, with a narrow particle size distribution, suitable for precision machining and uniform dispersion.   

-Specific surface area: The specific surface area is relatively low, usually between 1-5 m ²/g, indicating that the particle surface is relatively dense.   

-Density: The theoretical density is 3.97 g/cm ³, and the actual bulk density depends on the particle morphology and size distribution.   

-Hardness: The Mohs hardness is 9, second only to diamond, and it has extremely high wear resistance.   

-Melting point: up to 2050 ° C, suitable for applications in high-temperature environments.

3. Chemical properties

SAL30 has excellent chemical stability, acid resistance, alkali resistance, corrosion resistance, and exhibits inertness in most chemical environments.

2、 Preparation process of SAL30

The preparation of SAL30 usually includes the following steps:

1. Raw material selection

The raw materials for preparing SAL30 are usually industrial grade aluminum hydroxide (Al (OH) ∝) or high-purity alumina powder.

2. Calcination process

Calcination is a key step in the preparation of SAL30, with the main objective of converting aluminum hydroxide or gamma alumina into alpha alumina. The calcination process is divided into the following stages:

-Dehydration stage: At 200-400 ° C, aluminum hydroxide is dehydrated and converted into gamma alumina.   

-Phase transition stage: At 1200-1400 ° C, gamma alumina gradually transforms into alpha alumina.   

-Grain growth stage: At high temperatures, alpha alumina grains gradually grow and form a stable crystal structure.

3. Crushing and Grading

After calcination, the alumina block is crushed and classified to obtain the desired micro powder particle size distribution.

4. Surface treatment (optional)

According to application requirements, SAL30 can be surface modified by coating with silane coupling agents or organic polymers to improve its dispersibility and compatibility with other materials.

3、 Application areas of SAL30

1. Ceramic industry

SAL30 is an important raw material for high-performance ceramics, used in the preparation of structural ceramics, electronic ceramics, and bioceramics. Its high hardness and wear resistance make it an ideal material for cutting tools, bearings, and seals.

2. Refractory materials

SAL30, as an additive or main component in refractory materials, can improve the material's high temperature resistance and thermal shock resistance, and is widely used in metallurgy, glass, and cement industries.

3. Electronic industry

SAL30 is used to manufacture ceramic substrates, insulators, and electronic packaging materials. Its high purity and excellent electrical insulation performance meet the high requirements of electronic devices.

4. Catalyst carrier

Due to its high specific surface area and chemical stability, SAL30 is often used as a catalyst carrier and is widely used in the fields of petrochemicals, environmental protection, and energy.

5. Coatings and Coatings

SAL30, as a functional filler, can improve the wear resistance, corrosion resistance, and high temperature resistance of coatings, and is widely used in the aerospace, automotive, and construction fields.

6. Biomedical Sciences

SAL30 is used for the preparation of bioceramics and artificial joints, and its biocompatibility and wear resistance make it an ideal biomaterial.

4、 Advantages and Challenges of SAL30

1. Advantages

-High purity and excellent physical and chemical properties.   

-Widely applicable fields and market demand.   

-The preparation process is mature and easy to scale up production.

2. Challenge

-The high-energy calcination process increases production costs.   

-The dispersibility and surface modification technology of micro powder still need further optimization.   

-In some high-end applications, the particle size distribution and purity requirements for SAL30 are extremely high, making preparation difficult.

5、 Future Development Trends

1. Green preparation process

Develop low-energy and low pollution preparation processes, such as microwave calcination and plasma calcination, to reduce environmental impact.

2. Nanotechnology and functionalization

Research the nanoscale preparation technology of SAL30 and develop alumina micro powders with special functions such as antibacterial and conductive properties.

3. Intelligent application

Combining artificial intelligence and material design to optimize the performance of SAL30 in different applications, such as smart coatings and self-healing materials.

Conclusion

Calcined alumina micro powder SAL30, as a high-performance inorganic material, plays an important role in multiple industrial fields. With the continuous advancement of preparation technology and the increasing demand for applications, the research and development of SAL30 will continue to deepen, providing strong material support for industrial development.