WFA lapping powder F400 F600 for lapping of copper discs
White Fused Alumina (WFA) lapping powder in F400 and F600 grades represents the optimal choice for precision lapping of copper discs. Engineered to deliver consistent material removal, exceptional surface finish, and superior dimensional accuracy, this high-purity abrasive material addresses the unique challenges posed by copper—a soft, ductile metal prone to smearing, scratching, and surface deformation during conventional processing.
PHYSICAL PROPERTIES
| Specific Weight |
3.96 g/ cm3 |
| Mohs Hardness |
9.0 |
| Crystal form |
α-Al2O3 |
| Melting Point |
2250℃ |
TYPICAL CHEMICAL ANALISIS [%]
| Al2O3 |
Fe2O3 |
SiO2 |
FeO |
MgO |
CaO |
TiO2 |
Na2O |
K2O |
LOI |
| 99.2-99.6 |
0.03-0.10 |
≤0.02 |
/ |
≤0.01 |
≤0.01 |
/ |
0.20-0.30 |
≤0.02 |
< 0.09 |
Superior Abrasive Characteristics
White Fused Alumina is produced by melting high-purity alumina in an electric arc furnace at temperatures exceeding 2,000°C, resulting in a crystalline material of exceptional hardness (Mohs hardness of 9) and chemical purity. For copper disc lapping, the F400 and F600 grit sizes are particularly well-suited. According to the FEPA standard, F400 corresponds to an average particle size of approximately 35 microns, while F600 averages around 16 microns. This combination allows for a two-stage lapping process: F400 for rapid stock removal and flatness correction, followed by F600 for fine finishing to achieve mirror-like surfaces with minimal subsurface damage.
Engineered for Copper Processing
Copper’s inherent softness presents significant challenges in precision machining. Traditional abrasives often lead to embedded particles, surface smearing, or excessive heat generation. WFA lapping powder overcomes these limitations through its unique combination of properties:
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Sharp, Angular Particle Morphology: The blocky, sharp-edged particles provide controlled cutting action, effectively removing material without gouging or generating excessive frictional heat that could soften the copper surface.
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Friability: WFA particles fracture under pressure, continuously presenting fresh cutting edges. This self-sharpening characteristic ensures consistent lapping performance throughout the process cycle.
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Chemical Inertness: The high purity of WFA minimizes the risk of chemical reactions with copper surfaces, preventing discoloration or contamination that could compromise subsequent plating or coating operations.
Precision Results for Critical Applications
Copper discs are essential components in industries ranging from semiconductor manufacturing to electronics cooling systems and power transmission. Achieving the precise surface flatness, thickness uniformity, and low surface roughness required by these applications demands an abrasive capable of delivering repeatable results. WFA F400 and F600 lapping powder enables:
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Tight Dimensional Control: Consistent particle size distribution ensures uniform material removal across the entire disc surface, maintaining parallelism and thickness tolerances within microns.
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Surface Finish Excellence: The progressive refinement from F400 to F600 yields surface roughness values (Ra) below 0.2 microns, suitable for applications requiring high thermal conductivity or optical reflectivity.
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Burr-Free Edges: The controlled cutting action minimizes edge roll-over and burr formation, reducing secondary finishing operations.
Application Guidelines
For optimal results with copper discs, WFA lapping powder is typically suspended in oil-based or water-based carriers and applied to cast iron or ceramic lapping plates. Process parameters such as pressure, rotational speed, and slurry concentration should be optimized based on disc diameter and initial surface condition. The compatibility of WFA with various lapping vehicle formulations allows for tailored solutions that balance cutting efficiency with surface quality.
Whether utilized in high-volume production environments or precision engineering workshops, WFA lapping powder in F400 and F600 grades delivers the reliability, consistency, and superior surface quality demanded by modern copper disc lapping applications.
