White Fused Alumina Micropowder

Product Overview

White fused alumina micropowder is a premium fine abrasive made from high-purity industrial alumina by arc fusion above 2000℃, cooling and crystallization, mechanical crushing, acid washing and hydraulic overflow classification. Its main crystalline phase is α-Al₂O₃. The white powder offers high purity, good self-sharpening and strong cutting action. Available systems include Chinese W grades, FEPA F230-F3000 and JIS #240-#10000. Applications include precision grinding and polishing, blasting, premium refractories, electronics and semiconductors.

Technical Specifications

Chemical Specifications

Key Features

1. High purity and hardness for strong cutting action

White fused alumina micropowder contains ≥99.0% Al₂O₃ with very low impurities. Its Mohs hardness of 9.0 and greater hardness and friability than brown fused alumina provide strong cutting action on hardened steel, alloy steel, high-speed steel and high-carbon steel.

2. Narrow size distribution without coarse-particle scratches

Acid washing and multistage hydraulic overflow classification produce a narrow, precisely controlled particle-size distribution, excluding oversize particles that could scratch precision workpieces.

3. Excellent chemical stability and electrical insulation

The micropowder resists acid, alkali and high temperatures, with good thermal stability and electrical insulation for clean electronic and semiconductor applications.

4. Good self-sharpening and low grinding heat

Grains continuously fracture to expose fresh edges, providing strong grinding action and low heat generation to reduce burning and improve surface quality.

5. Pure white color preserves workpiece appearance

The pure white product is free from rust and similar impurities and suits blasting and grinding where iron residue is prohibited, without affecting workpiece color.

Process Overview

Process stage and description

Raw materials: low-sodium, high-purity alumina powder (Al₂O₃≥99.5%)

Fusion: electric arc furnace above 2000℃

Crystallization: natural cooling to form large α-Al₂O₃ crystals

Crushing and milling: mechanical crushing followed by powder milling

Acid washing: removal of magnetic and other impurities

Hydraulic classification: precise multistage overflow classification

Drying and packaging: drying followed by standard packaging

Available Grit Sizes

See attachment

Typical Applications

Precision grinding and polishing: thinning and polishing silicon / silicon carbide wafers, piezoelectric crystals, optical lenses and precision instrument parts; mirror polishing stainless steel at 8000-10000 grit; surface grinding and polishing glass, stone, aluminum and copper

Blasting: blasting and lapping, particularly wet blasting; television screen processing, dental mold cleaning, and frosted finishes on polyresin and acrylic crafts

Bonded and coated abrasives: superfinishing stones, metallographic sandpaper, polishing wheels and lapping compounds

Precision casting: molding sand

Premium refractories: high-grade refractory products, ceramic additives and specialty ceramics

Emerging applications: lithium-battery separator coatings, 3D printing materials, wear-resistant coatings and floor paints, and industrial ceramics such as ceramic filter plates and honeycomb ceramics

Packaging

Packaging type

Standard bags: 25 kg lined woven bags

Premium packaging: 20 kg bags, adjustable on request

Custom packaging: special packaging on request

Neutral or branded packaging is available on request.

Storage Recommendations

To maintain white fused alumina micropowder quality during storage, observe the following conditions:

Store in a cool, dry, ventilated warehouse away from direct sunlight. Relative humidity should preferably be ≤60% to prevent powder caking and mold on packaging.

Stack bags no more than 10 layers high to prevent packaging damage or grain fracture. Use wooden or plastic pallets to keep them off the ground.

Keep separate from acids, alkalis, organic solvents and other corrosive substances. Store different grit sizes separately with clear labels to prevent mixing.

Follow first-in, first-out (FIFO) stock rotation to avoid prolonged storage.

Before use, check that the micropowder packaging is intact and verify the specification label to prevent incorrect selection.