SUOYI manufactures 99Al2O3 alumina ceramic powder.

SUOYI manufactures 99Al2O3 alumina ceramic powder.

Alumina ceramic powder is a white inorganic powder with α-alumina (α-Al₂O₃) as its main crystalline phase. It is a core raw material for preparing alumina structural ceramics and electronic ceramics. Commonly known in the industry as high-alumina ceramic powder, its grades are distinguished by purity, particle size, and formulation. The mainstream grades are 85%, 95%, 99%, and 99.5% high-purity ceramic powder, suitable for various molding processes such as dry pressing, hot pressing, casting, slip casting, and isostatic pressing.

1. Alumina Ceramic Powder Composition Classification (Mainstream Grades)

1.1 85% Ceramic Powder: Al₂O₃≈85%, with the balance composed of SiO₂, CaO, and MgO sintering aids. Sintering temperature: 1280~1350℃. Lowest cost.

1.2 95% Ceramic Powder: Al₂O₃ ≥ 95%, with approximately 5% additives (silicon, calcium, magnesium oxides). Largest industrial application, sintering temperature around 1500℃, optimal cost-performance ratio.

1.3 99% Ceramic Powder: Al₂O₃ ≥ 99%, with trace amounts of MgO/Y₂O₃ grain stabilizers, impurities at the ppm level, sintering temperature 1530~1580℃, for precision parts.

1.4 99.5/99.9 High-Purity Ceramic Powder: Al₂O₃ ≥ 99.5%~99.99%, low-sodium, low-silicon ultrafine powder, raw material for electronic substrates, transparent ceramics, and semiconductor components.

2. Core Physicochemical Properties of Alumina Ceramic Powder

2.1 Mechanical Properties: Mohs hardness 9 (second only to diamond); 95% alumina ceramic sintering density 3.65~3.75 g/cm³, flexural strength 300 MPa; 99% alumina ceramic density 3.85~3.95 g/cm³, flexural strength ≥500 MPa, excellent wear resistance.

2.2 Heat Resistance: Melting point 2050℃, long-term service temperature 1500℃, low coefficient of thermal expansion, resistant to rapid temperature changes.

2.3 Corrosion Resistance: Resistant to strong acids, alkalis, and organic solvents; strong chemical inertness.

2.4 Electrical Properties: Excellent insulation, low dielectric loss, stable high-frequency insulation, making it the preferred raw material for electronic insulation.

2.5 Powder Parameters: Standard D50 0.4~3μm, customizable nano-sized (0.2μm), granulated spherical powder (good flowability, suitable for fully automatic dry pressing).

3. Advantages of Alumina Ceramic Powder

3.1 Stable Sintering: Uniform premixed additives ensure controllable sintering shrinkage (11%~14%), resulting in high dimensional consistency and reducing cracking and porosity.

3.2 Versatile Molding: Available in various forms including cast iron powder, hot-pressed casting powder, dry-pressed granulation powder, and fine injection powder, allowing for customized particle size and bonding systems.

3.3 Strict Impurity Control: Extremely low Fe₂O₃ and Na₂O content prevents ceramic blackening and insulation failure; high-purity powder has a sodium content ≤5ppm.

3.4 Differentiated Cost-Effectiveness: 85/95% pure powder reduces production costs, while 99% pure powder meets the needs of precision and high-end manufacturing.

4. Application Areas of Alumina Ceramic Powder

4.1 Electronic Ceramics (95/99% pure powder is the mainstay): Power device substrates, IGBT insulating substrates, resistor substrates, ceramic terminals, high-voltage insulators, MLCC dielectric ceramic components, and sensor ceramic housings. 4.2 Wear-resistant mechanical ceramics (95/99% ceramic powder)
Ceramic plungers, water valve ceramic discs, sealing rings, textile ceramic yarn guides, grinding media balls, sandblasting nozzles, bearing sleeves.

4.3 Chemical/High-temperature resistant ceramics
Corrosion-resistant ceramic pipe fittings, crucibles, high-temperature furnace tubes, catalyst carriers, corrosion-resistant pump body parts.

4.4 High-end precision (99.5%+ high-purity powder)
Semiconductor wafer components, medical ceramics (dental posts, surgical accessories), transparent alumina lamp tubes, aerospace insulating components.

5. Alumina Ceramic Powder Forming

- Dry-pressed granulated powder: Spray-granulated spherical form, excellent flowability, mass production with fully automated presses;

- Hot-pressed casting powder: Ultrafine + low-temperature additives, wax slurry molding, for complex and irregularly shaped small parts;

- Casting powder: Ultrafine narrow particle size distribution, for ultra-thin substrate production;

- Firing: 95% alumina ceramic powder 1480~1520℃, 99% alumina ceramic powder 1530~1580℃, high-purity alumina ceramic powder above 1600℃.

6.
- General wear-resistant and general-purpose insulating parts → 95% alumina ceramic powder (preferred for cost-effectiveness)

- Precision wear-resistant and high-voltage electronic parts → 99% alumina ceramic powder

- Ultra-thin substrates, semiconductors, medical ceramics → 99.5% and above high-purity ultrafine alumina ceramic powder

- Low-end refractory and coarse ceramic parts → 85% alumina ceramic powder