Factory Direct Calcined Alumina Supplier with Low Na₂O, Controlled D50 Grain

HUAO Calcined Alumina Fine Powder is processed from carefully selected low-sodium raw materials through precision micro-grinding and advanced refining technologies. Produced in our ISO 9001, ISO 14001, and ISO 45001 certified manufacturing facility, our calcined alumina offers a high degree of alpha-phase conversion (α-Al₂O₃ ≥ 93-94%) and high density (up to ≥ 3.94 g/cm³). As a professional China calcined alumina manufacturer with over 10 years of global B2B export experience, HUAO delivers consistent, stable-grade micro-powders designed to satisfy demanding requirements across advanced structural ceramics, electronic substrates, refractories, and high-precision polishing applications.

Note: Grain size distribution (D50) and mesh specifications can be prepared according to specific customer requirements.

• Controlled Low Sodium Content
  Low alkali levels (Na₂O ≤ 0.15% for HA-2 grade) prevent dielectric breakdown and improve electrical insulation properties in electronic components.
• High α-Phase Transition & Density
  Complete calcination produces a dominant α-Al₂O₃ crystal structure (≥ 94%) with high true density (≥ 3.94 g/cm³), providing superior structural compaction.
• Exceptional Mechanical Hardness
  High intrinsic crystal hardness delivers maximum resistance against severe sliding abrasion and mechanical wear in heavy-duty industrial settings.
• Thermal Stability & Conductivity
  A high melting point guarantees volume stability under high operating temperatures, while high thermal conductivity facilitates rapid heat dissipation.
• Tight Particle Size Control
  Narrow particle size distribution (D50: 4-5 μm; 325 mesh residue ≤ 1%) ensures high dispersion uniformity, smooth sintering shrinkage, and optimized rheology.

• Architectural & Structural Ceramics
  Improves microstructural packing density, mechanical strength, fracture toughness, and surface finish in wear-resistant ceramic tiles, structural components, and machinery linings.
• Electronic Substrates & Insulators
  Provides high electrical resistivity and superior thermal dissipation, making it ideal for ceramic substrates, spark plugs, and electronic insulating components.
• Refractories & High-Temperature Linings
  Enhances hot strength, volume stability, and thermal shock resistance in high-alumina bricks, monolithic castables, and specialized kiln refractory systems.
• Wear-Resistant Items & Polishing Media
  Serves as a high-efficiency polishing abrasive and raw material for wear components, delivering fast stock removal and precise surface finishing.

• Certified Production & Quality Assurance
  Operating strictly under ISO 9001 (Quality Management), ISO 14001 (Environmental Management), and ISO 45001 (Occupational Health & Safety) systems, HUAO provides full product traceabilities and stringent batch consistency for every shipment.
• Refined Low-Sodium Processing
  Advanced micro-grinding and refining technologies allow us to supply ultra-pure grades (Al₂O₃ ≥ 99.6%, Na₂O ≤ 0.15%) designed for high-end electronics and specialized ceramics.
• Direct Factory Source with Export Experience
  With over a decade of overseas supply experience, HUAO acts as an active quality supervisor to monitor production progress, batch testing, and port handling.
• Flexible Particle Tailoring
  Fine-grinding lines allow particle sizes (D50) and mesh distributions to be custom-milled to seamlessly align with client slip casting, pressing, or compounding recipes.

HUAO provides versatile grain size preparation (D50 range, sub-micron powder milling) and customizable particle grading based on client requests. Standard B2B packaging options include 25kg paper bags, 50kg bags, as well as 1000kg and 1250kg jumbo bulk bags (ton bags) with customized moisture-barrier protection for export shipping.

A1: HA-2 features higher chemical purity (Al₂O₃ ≥ 99.6%), lower soda content (Na₂O ≤ 0.15%), a higher α-Al₂O₃ phase (≥ 94%), and higher density (≥ 3.94 g/cm³) compared to HA-1, making HA-2 ideal for electronic substrates and advanced technical ceramics.

A2: Yes, while our standard D50 ranges between 4-5 μm, HUAO provides custom grinding and classification to meet specific grain size distributions required by our clients' production lines.

A3: HUAO operates as a fully certified calcined alumina manufacturer under ISO 9001, ISO 14001, and ISO 45001 management systems to guarantee batch-to-batch quality stability.

A4: We offer direct factory shipments in 25kg or 50kg bags, 1000kg/1250kg jumbo ton bags, or specialized palletized packaging tailored to client unloading preferences.

We also provide other alumina products. If you would like to learn more about Tabular Alumina, please click here.