Aluminum Oxide (Alumina) Lapping Sheet for Precision Finishing

What Is an Aluminum Oxide Lapping Sheet?

An Aluminum Oxide Lapping Sheet is a precision-coated abrasive film made by depositing micron-graded Al₂O₃ particles onto a high-strength polyester backing. It is widely used in industries requiring controlled material removal, high surface quality, and tight tolerance finishes.

Key Features

Why Use Aluminum Oxide Lapping Sheets?

Common Applications

How to Use Aluminum Oxide Lapping Sheet

Manual Polishing

1. Mount the sheet on a flat glass, metal, or granite platen

2. Apply water or alcohol-based fluid (if wet use is preferred)

3. Rub the workpiece in a figure-8 or circular motion

4. Use light, even pressure; inspect surface regularly

Machine Polishing

1. Affix the sheet to polishing platen (PSA backing or vacuum)

2. Use a jig or fixture for consistent contact and angle

3. Apply appropriate pressure (based on material)

4. Use in grit sequence: e.g. 30 µm → 15 µm → 9 µm → 3 µm → 1 µm 

Best Practices

• Always clean the workpiece and film before use

• Store sheets flat in dust-free packaging

• Don’t reuse sheets once the abrasive is worn out

• Use fresh sheets for each grit step to prevent cross-contamination

• Combine with appropriate lapping slurry if required for enhanced performance

 Example Grit Sequence for Precision Metal Finishing

Finish Quality

• Achievable surface finish: Ra < 0.02 µm

• Flatness and uniformity ideal for optical-grade finishes

Would you like:

• A sample sheet polishing process for your material (e.g. stainless steel, fiber ferrules)?

• Help choosing the right grit sizes for your use case?

• A comparison with diamond or SiC lapping sheets?