Diamond Polishing Compound and Paste for Metallographic Sample Preparation

Beta Diamond Products diamond polishing compounds are oil-soluble synthetic diamond formulations engineered for metallographic lapping, intermediate polishing, and precision surface preparation. Available in particle sizes from 45 micron (coarse) through 0.1 micron (sub-micron), in oil-soluble, water-soluble, and universal formulations, our compounds are used by materials science laboratories, aerospace quality control departments, semiconductor fabs, and medical device manufacturers requiring consistent, batch-reproducible polishing results.

Standard Diamond Polishing Compound Sequence for Metallography

A complete diamond polishing sequence using compound typically proceeds as follows. After the final grinding step (1200 grit SiC or equivalent), transition to:

1. 9 micron diamond compound on a hard woven cloth (e.g., LECO Texmet, Buehler TexMet, or equivalent) — removes grinding scratches, establishes planar surface
2. 3 micron diamond compound on a medium nap cloth — refines surface, removes 9μm scratches
3. 1 micron diamond compound on a low-nap or silk cloth — near-final diamond polish
4. 0.25 micron diamond compound on a low-nap cloth — final diamond polish before oxide step if required
5. Oxide polishing (colloidal silica or alumina, sold separately) on a chemomechanical cloth — for EBSD, SEM, and deformation-sensitive applications only

Each step should be performed until scratches from the previous step are completely eliminated, verified by examination at 50–100× magnification under reflected light.

Compound Formulations Available

• Oil-soluble (standard) — compatible with all polishing cloths; preferred for manual polishing and extended polishing cycles where evaporation must be minimized
• Water-soluble — preferred for automated systems and applications requiring aqueous cleanup; not suitable for reactive metals (Mg, U) in aqueous environments
• Universal — compatible with both oil and water lubricants; provides flexibility across different preparation steps and equipment configurations

Custom Formulations

Beta Diamond Products manufactures diamond compound to specification for non-standard requirements: custom micron sizes from 0.1 to 120 microns, custom packaging volumes, alternative carrier chemistries, and high-concentration formulations for extended lapping operations. Contact our technical team for custom compound specifications and minimum order quantities.

Frequently Asked Questions

How do I apply diamond compound to a polishing cloth?

Apply a small quantity of compound (approximately 3–5mm ribbon from the syringe tip) to the center of the rotating polishing cloth. Spread by allowing the cloth to distribute the compound for 10–15 seconds before applying the specimen. Apply 2–4 drops of the compatible lubricant (oil or water, matched to compound formulation) every 3–5 minutes during extended polishing cycles to maintain cut rate and prevent the compound from drying. For automated systems, consult the system manual for recommended compound application intervals.

What lubricant should I use with diamond compound?

Use a lubricant matched to the compound formulation: oil-based lubricant (such as kerosene, mineral oil, or proprietary polishing lubricant) for oil-soluble compounds; distilled water for water-soluble compounds; either for universal compounds. The lubricant prevents the compound from drying on the cloth and maintains the suspension of diamond particles in the polishing zone. Proprietary polishing lubricants available from Buehler (Blue Lube), Struers (Blue, Red), and LECO are compatible with Beta Diamond compounds — or contact us for recommendations.