NFZ System (NANO-FEMTO-ZETA-RC)
Complete automated grinding and polishing workflow with precise control for monocrystalline diamond polishing and final finishing steps.
Key Considerations
Choose the Right Viscosity
High-viscosity for rapid removal; low-viscosity for fine control or sensitive samples.
Use Compatible Pads
Pair with low-nap or resilient pads for optimal flatness and abrasive efficiency.
Control Force and Duration
Single-crystal particles produce consistent scratch depth. Use moderate pressure and standard cycle times to preserve flatness and surface finish.
Introduction
Monocrystalline diamond polishing plays a vital role in producing clean, high-resolution surface finishes in metallographic sample preparation. Composed of single-crystal diamond particles with uniform, angular geometry, these abrasives deliver predictable, repeatable cutting action that is well suited for intermediate and final polishing on metals, hardened steels, and edge-critical samples. Monocrystalline diamond pairs well with low- to medium-napped polishing pads to maintain planarity and minimize smearing. Proper selection of abrasive size, suspension medium, and compatible lubrication ensures precise polishing with consistent material removal and excellent edge retention.
Diamond Abrasive Selection Guidelines
This reference outlines best-practice abrasive sizes for rough and final polishing across metals, ceramics, and composite materials. Proper abrasive selection is critical to ensure accurate microstructural representation, prevent surface damage, and optimize polishing efficiency.
Preferred Abrasive
Acceptable Alternative
Not Typically Recommended
Polishing Guide for Metals
| Metal | Rough Polishing (Diamond) | Final Polishing (Oxide) | ||||
|---|---|---|---|---|---|---|
| Abrasive Size | 9 µm | 6 µm | 3 µm | 1 µm | Al2O3 | SiO2 |
| Aluminum | ||||||
| Copper / Brass | ||||||
| Stainless Steel | ||||||
| Soft Steel | ||||||
| Hard Steel | ||||||
| Tool Steel | ||||||
| Titanium | Etch Polish | |||||
| Zinc, Tin, Lead | ||||||
Polishing Guide for Ceramics and Composites
| Ceramic / Composite | Coarse Grind | Fine Grind | Rough Polish | Fine Polish | ||
|---|---|---|---|---|---|---|
| Diamond Size | 30 µm | 15 µm | 9 µm | 6 µm | 3 µm | 1 µm + SiO2 |
| Alumina | ||||||
| Silicon Nitride | ||||||
| Polymer Composite | ||||||
| Metal Matrix Composite | ||||||
| Ceramic Matrix Composite | ||||||
| Cermet | ||||||
Note: These selections reflect proven laboratory procedures balancing speed, flatness, and structure preservation. Adjust abrasive types and sequence for material-specific variables such as grain size, hardness, and thermal sensitivity.
Polymer composites: Diamond can embed in soft polymer matrices and carry through to subsequent steps. For polymer-dominated samples, SiC grinding (through P2400 or P4000) followed directly by alumina or colloidal silica is often preferred. Reserve diamond polishing for fiber- or filler-dominated composites where the matrix can tolerate it.
Polishing Pad Selection Guideline
| Pad Image & Link | Use Case | Pad Icon | Polishing Stage |
|---|---|---|---|
|
CERMESH metal mesh pad used for semi-fixed abrasive coarse to intermediate lapping. Excellent for initial removal of damage from sectioning and hard materials. |
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Coarse / Intermediate |
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POLYPAD is a durable synthetic polyester pad ideal for intermediate polishing, especially with 6-15 µm diamond abrasives. Designed as a long-life nylon alternative. |
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Intermediate |
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TEXPAN is a widely used non-woven intermediate polishing pad, compatible with most diamond suspensions. Effective across a broad range of materials. |
|
Intermediate |
|
Black CHEM 2 is a porometric polymer pad with rubber-like consistency, offering balanced action between low and high nap pads. Ideal for moderate nap intermediate polishing. |
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Intermediate |
|
DACRON II is a non-napped woven polishing pad widely used in Europe for intermediate steps on metals. Suitable for 1-15 µm diamond abrasives. |
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Intermediate |
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NYPAD is a low-napped nylon pad tailored for intermediate polishing of harder metals and alloys. Performs well with mid-size diamond abrasives. |
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Intermediate |
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GOLD PAD is a low-napped pad ideal for 1-9 µm polishing. Designed for consistent material removal and flatness control during final pre-polishing. |
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Intermediate |
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ATLANTIS is a woven low-nap final polishing pad with foam backing for enhanced compliance. Ideal for 1-6 µm diamond. Great for critical surface flatness needs. |
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Final |
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MICROPAD is a high-napped final polishing pad ideal for producing a mirror finish on metals and polymers. Recommended for <1 µm diamond or colloidal silica. |
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Final |
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TRICOTE is a tight high-napped final polishing pad for metals. Offers better control of surface texture and minimal abrasive drag. |
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Final |
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NAPPAD is a very high-napped final polishing pad tailored for soft metals and polymers. Provides gentle polishing action to minimize pull-out and relief. |
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Final |
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MOLTEC 2 is a wool-based final polishing cloth used when edge retention is not critical. Works well with alumina and colloidal silica on metals. |
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Final |
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FELT PAD is a thick final polishing pad made for large samples or glass. Ideal for use with colloidal silica or alumina slurries where surface uniformity is key. |
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Final |
Process Description
Monocrystalline diamond polishing is typically performed in one or more stages to refine the surface after grinding or polycrystalline rough polishing. The uniform single-crystal particles produce consistent scratch geometry, making this abrasive well suited for intermediate and final polishing on metals and hard materials, especially where edge retention and surface finish matter. Use coarser grades for intermediate refinement and finer grades for the final surface. To preserve flatness and finish quality, polishing time and pressure should be carefully controlled.
Minimizing Polishing Artifacts
To reduce edge rounding, relief, and embedding during monocrystalline diamond polishing:
- Choose the correct abrasive size and viscosity for the material and stage
- Use low-nap or non-woven pads to support flat, uniform surfaces
- Ensure platens are flat and runout is under 2.5 µm (for 8" discs)
- Apply even pressure and limit polishing durations to avoid over-polishing
Recommended Procedures
- Secure the polishing pad firmly onto a flat, clean platen
- Pre-charge the pad with monocrystalline diamond suspension or paste, working it into the surface for consistent cutting from the start of the cycle
- Dispense additional diamond at a rate of 1-2 drops every 10-15 seconds during polishing, depending on speed and sample area
- Introduce a compatible lubricant to reduce heat and optimize abrasive performance
- For ceramic and mineral specimens, alternate diamond and colloidal silica (e.g., SIAMAT) for enhanced chemomechanical polishing (CMP)
- Begin polishing with moderate force to leverage the sharp, angular cutting action of monocrystalline diamond
- At the end of the step, rinse the specimen thoroughly with water followed by ethanol before drying
- After polishing, rinse specimens thoroughly and dry completely before microscopic inspection
Monocrystalline Diamond Suspensions (water-based)
| Description | Quantity | Low Viscosity | High Viscosity | Product Image |
|---|---|---|---|---|
| 1 micron (blue) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1001-250 GMA-1001-500 GMA-1001-1GL |
MA-1001-250 MA-1001-500 MA-1001-1GL |
 |
| 3 micron (green) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1003-250 GMA-1003-500 GMA-1003-1GL |
MA-1003-250 MA-1003-500 MA-1003-1GL |
 |
| 6 micron (yellow) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1006-250 GMA-1006-500 GMA-1006-1GL |
MA-1006-250 MA-1006-500 MA-1006-1GL |
 |
| 9 micron (red) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1009-250 GMA-1009-500 GMA-1009-1GL |
MA-1009-250 MA-1009-500 MA-1009-1GL |
 |
| 15 micron (brown) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1015-250 GMA-1015-500 GMA-1015-1GL |
MA-1015-250 MA-1015-500 MA-1015-1GL |
 |
| 30 micron (orange) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1030-250 GMA-1030-500 GMA-1030-1GL |
MA-1030-250 MA-1030-500 MA-1030-1GL |
 |
| 45 micron (purple) DIAMAT Monocrystalline diamond | 250 ml 500 ml 1 gallon |
GMA-1045-250 GMA-1045-500 GMA-1045-1GL |
MA-1045-250 MA-1045-500 MA-1045-1GL |
 |
Monocrystalline Diamond Paste
| Description | Quantity | Catalog Number | Product Image |
|---|---|---|---|
| DIAMAT Monocrystalline diamond paste (0.25 micron) | 5 gm 20 gm |
MA-0225-05 MA-0225-20 |
 |
| DIAMAT Monocrystalline diamond paste (0.50 micron) | 5 gm 20 gm |
MA-0250-05 MA-0250-20 |
|
| DIAMAT Monocrystalline diamond paste (1 micron) | 5 gm 20 gm |
MA-2001-05 MA-2001-20 |
 |
| DIAMAT Monocrystalline diamond paste (3 micron) | 5 gm 20 gm |
MA-2003-05 MA-2003-20 |
 |
| DIAMAT Monocrystalline diamond paste (6 micron) | 5 gm 20 gm |
MA-2006-05 MA-2006-20 |
 |
| DIAMAT Monocrystalline diamond paste (9 micron) | 5 gm 20 gm |
MA-2009-05 MA-2009-20 |
 |
| DIAMAT Monocrystalline diamond paste (15 micron) | 5 gm 20 gm |
MA-2015-05 MA-2015-20 |
 |
| DIAMAT Monocrystalline diamond paste (30 micron) | 5 gm 20 gm |
MA-2030-05 MA-2030-20 |
 |
Diamond Extenders (Lubricants)
| Description | Quantity | Catalog Number | Product Image |
|---|---|---|---|
| DIALUBE Diamond Extender | 16 oz (0.125L) 32 oz (0.24L) 1 gallon (3.8L) |
DL-3000-16 DL-3000-32 DL-3000-128 |
|
| DIALUBE Blue Alcohol Lubricant | 16 oz (0.125L) 32 oz (0.24L) 1 gallon (3.8L) |
AOD-3000-16 AOD-3000-32 AOD-3000-128 |
|
| DIALUBE Purple Alcohol Lubricant | 16 oz (0.125L) 32 oz (0.24L) 1 gallon (3.8L) |
ADL-3000-16 ADL-3000-32 ADL-3000-128 |
|
| POLYLUBE Non-Aqueous Diamond Extender | 16 oz (0.125L) 32 oz (0.24L) 1 gallon (3.8L) |
PDL-3000-16 PDL-3000-32 PDL-3000-128 |
|
| POLYLUBE Red (Anti-Corrosion) Lube | 16 oz (0.125L) 32 oz (0.24L) 1 gallon (3.8L) |
PDL-3000R-16 PDL-3000R-32 PDL-3000R-128 |
Troubleshooting
| Symptom | Cause | Solution |
|---|---|---|
| Coarse Scratching | Old or contaminated suspension; excessive abrasive pressure | Use fresh monocrystalline suspension; reduce applied force |
| Uneven Material Removal | Poor abrasive distribution or inconsistent pad contact | Ensure even application of suspension; verify flat, stable platen setup |
| Pad Glazing | Diamond buildup or insufficient flushing | Flush regularly with water or alcohol; condition or replace pad |
| Edge Rounding | Over-polishing or inappropriate pad compliance | Reduce polishing time; use a firmer pad to maintain edge definition |
| Low Material Removal Rate | Low abrasive loading or degraded diamond suspension | Reapply suspension more frequently; check expiration of abrasive |
| Specimen Drag or Pad Tearing | Insufficient lubrication with high downforce | Increase lubricant volume; reduce pressure |
| Surface Smearing or Pull-Out | Overly aggressive grit size for specimen material | Switch to finer monocrystalline grit; ensure pad matches application |
Related Equipment
GIGA-S Vibratory Polisher
High-capacity vibratory polishing system for batch processing with monocrystalline diamond abrasives.
Frequently Asked Questions
Common questions about monocrystalline diamond polishing
What is the difference between monocrystalline and polycrystalline diamond?
Monocrystalline diamond consists of single-crystal particles with uniform, blocky geometry, providing sharp cutting edges and consistent polishing performance. Polycrystalline diamond has multiple crystal structures with irregular shapes, offering aggressive cutting for rapid material removal. Monocrystalline is preferred for controlled, fine polishing and superior surface finish, while polycrystalline excels at rough polishing of hard materials.
Which materials benefit most from monocrystalline diamond polishing?
Monocrystalline diamond is ideal for metals requiring high-quality surface finish including stainless steel, tool steel, hard steel, and precious metals. It's also excellent for ceramics, semiconductors, and composite materials where fine polishing and minimal surface damage are critical. For very hard materials like carbides, monocrystalline provides better control and less aggressive cutting compared to polycrystalline diamond.
What is the best particle size for final polishing with monocrystalline diamond?
For final polishing, 1 µm monocrystalline diamond is the standard choice for most metals and hard materials. For ultra-fine surfaces, 0.25-0.5 µm monocrystalline diamond provides exceptional results with minimal scratching. Always follow diamond polishing with a colloidal silica or alumina final step for the best microstructural revelation and surface quality.
Should I use low-viscosity or high-viscosity monocrystalline diamond?
Low-viscosity suspensions (DIAMAT GMA series) provide excellent heat dissipation and uniform abrasive distribution, ideal for automated polishing and extended polishing cycles. High-viscosity suspensions and pastes (DIAMAT MA series) offer concentrated abrasive delivery and longer working time, preferred for manual polishing or when frequent reapplication is impractical. Choose based on your equipment, material, and workflow preferences.
How do I prevent edge rounding with monocrystalline diamond polishing?
To minimize edge rounding, use low-nap or non-woven polishing pads that provide firm support. Reduce polishing time and pressure, especially with finer diamond grades. Ensure your platen is perfectly flat with minimal runout. Consider using rigid composite pads or magnetic polishing systems for critical edge retention. Inspect samples frequently and stop polishing as soon as the desired surface finish is achieved.
Can I use monocrystalline diamond on soft metals like aluminum and copper?
Yes, monocrystalline diamond works well on soft, ductile metals when used with fine particle sizes (1-3 µm) and appropriate techniques. Use low pressure, short polishing times, and low-nap pads to prevent smearing and relief. For aluminum and copper alloys, start with 3 µm monocrystalline, then finish with 1 µm diamond followed by colloidal silica for optimal results. Avoid coarse diamond grades that can cause excessive material removal and surface damage.