Coated Abrasive Grains

Product Specification: Iridium-Coated Alundum (Coated Abrasive Grains)

1. Product Overview
Iridium-Coated Alundum is a high-performance modified abrasive developed from premium White Fused Alumina (WFA) or Brown Fused Alumina (BFA). Through advanced high-temperature coating technology, a layer of Iridium-based composite material (typically Iridium Oxide) is deposited onto the surface of the abrasive grains. This process creates a "soft coating" on the grain surface, fundamentally enhancing the traditional characteristics of the abrasives media.

2. Key Characteristics
*   Appearance: Red, Yellow, or White (depending on the base grain and coating process).
*   Base Material: High-purity White or Brown Fused Alumina.
*   Coating Composition: Metal Iridium and Iridium Oxide composite layer.
*   Hardness: High micro-hardness (increased by approx. 10% compared to standard grains).
*   Toughness: Significantly improved (increased by approx. 10%), reducing grain breakage.
*   Surface Texture: The coating process creates a rougher surface morphology.
*   Thermal Properties: Excellent heat dissipation capability and resistance to thermal shock.

3. Manufacturing Process
1.  Selection of Base Grains: Only high-quality, sharp-edged White or Brown Fused Alumina grains are selected as the substrate.
2.  Surface Activation: The grain surfaces are treated to ensure optimal adhesion of the coating.
3.  High-Temperature Coating: The grains are introduced into a high-temperature reaction chamber where a metal-organic precursor is decomposed, depositing a uniform layer of Iridium/Iridium Oxide onto the grain surface.
4.  Heat Treatment (Calcination): The coated grains undergo a specific calcination process. This step ensures the coating is firmly bonded to the substrate, forming a stable composite structure without altering the core properties of the abrasive.

4. Available Grades and Specifications
We offer a range of Iridium-Coated Alundum products to suit various applications:
*   White Iridium-Coated Alundum: For high-precision grinding and light-colored products.
*   Red/Brown Iridium-Coated Alundum: For heavy-duty grinding and cutting applications.
*   Particle Sizes: Available in standard FEPA (F4 - F220) and ANSI grit sizes.
*   Chemical Composition (Typical):
    *   Al₂O₃: 99.0% Min (Base)
    *   Coating (Ir/IrO₂): Controlled percentage to optimize performance.

5. Primary Applications
Iridium-Coated Alundum is the ideal choice for manufacturing high-end bonded and coated abrasives:
*   Bonded Abrasives:
    *   Cutting-Off Wheels: Significantly extends service life and reduces burning of the workpiece.
    *   Grinding Wheels: Used for precision grinding of tools, bearings, and automotive parts.
    *   Resin Grinding Discs: Offers a cooler cut and higher material removal rate.
*   Coated Abrasives:
    *   Sandpaper/Sand belts: Used in high-performance sanding applications where durability is critical.
*   Refractory & Specialty Applications:
    *   Precision investment casting.
    *   High-performance refractory materials.
    *   Spray coating materials.

6. Advantages over Conventional Alundum
*   Enhanced Bonding Strength: The rough, coated surface provides superior mechanical interlock and chemical affinity with resin, ceramic, and rubber bond systems.
*   Increased Durability: The service life of abrasive tools is extended by 30-50%.
*   Higher Grinding Efficiency: Improved self-sharpening characteristics lead to faster cutting speeds (approx. 30% increase).
*   Cooler Grinding: The coating acts as a thermal barrier and improves chip clearance, preventing workpiece burn.
*   Superior Hydrophilicity: The coating increases the wettability of the grains, which is beneficial for coolant penetration in wet grinding operations.

7. Packaging and Storage
*   Packaging: 25kg multi-wall paper bags with moisture-proof liner. Custom packaging (e.g., 500kg/1000kg bulk bags) is available upon request.
*   Storage: Store in a dry, indoor environment. Protect from moisture and direct contact with the ground.

Note: This specification is based on industry-standard "Iridium-Coated" Alundum technology. For specific technical data sheets (TDS) and safety data sheets (SDS), please contact our sales department.