Where PCD beats carbide — and where it does not
PCD is the clear choice for high-silicon (hypereutectic) aluminium alloys, metal-matrix composites (MMC) and long production runs of finished aluminium parts, where abrasive wear destroys uncoated carbide edges within minutes.
PCD is not suitable for ferrous materials: at cast iron and steel cutting temperatures, carbon diffuses into the iron and the edge fails rapidly. For ferrous work, PCBN is the superhard option.
Recommended cutting conditions by grade (Koves catalogue)
Official PCD cutting conditions from the Koves catalogue, covering aluminium alloys, copper alloys, wood and tungsten carbide.
For hypereutectic Al–Si alloys the catalogue recommends KPD10 / KPD25 across the whole Si range; lower Si contents allow higher speeds.
| Workpiece material | Vc (m/min) | f (mm/rev) | ap (mm) | Recommended grades |
|---|---|---|---|---|
| Aluminium alloy (Si 8-14%) | 1000–3000 | 0.1–0.8 | ≤ 3 | KPD10 / KPD25 |
| Aluminium alloy (Si 9-14%) | 800–2500 | 0.1–0.5 | ≤ 3 | KPD10 / KPD25 |
| Aluminium alloy (Si >14%) | 300–700 | 0.1–0.4 | ≤ 3 | KPD10 / KPD25 |
| Aluminium alloy (high Si >18%) | 300–700 | 0.1–0.4 | ≤ 3 | KPD10 / KPD25 |
| Copper alloys | ~1000 | 0.05–0.2 | ≤ 3 | KPD10 / KPD25 |
| Carbide (pre-sintered) | ~1000 | 0.1–0.3 | ≤ 2 | KPD10 / KPD25 |
| Wood | ~4800 | 0.1–0.4 | – | KPD10 / KPD25 |
| Carbide (sintered) | 10–50 | ~0.2 | ≤ 0.5 | KPD05 / KPD10 |
Typical starting parameters
The ranges below are industry-typical starting points for positive-geometry PCD turning inserts; Koves confirms final parameters against your alloy, clamping and machine.
| Workpiece material | Cutting speed Vc (m/min) | Feed f (mm/rev) | Depth of cut ap (mm) | Coolant |
|---|---|---|---|---|
| Wrought aluminium (1xxx–7xxx) | 500–3000+ | 0.05–0.35 | 0.1–3.0 | Dry / MQL / flood |
| Cast Al–Si < 10% Si | 400–2000 | 0.05–0.30 | 0.1–2.5 | Dry / MQL / flood |
| Hypereutectic Al–Si (15–25% Si) | 150–600 | 0.05–0.20 | 0.05–1.5 | MQL / flood |
| Metal-matrix composite (MMC) | 100–400 | 0.05–0.15 | 0.05–1.0 | Flood |
Edge preparation and grades
Sharp, honed PCD edges give the best finish on wrought alloys; lightly honed or chamfered edges survive interrupted cuts and MMC better.
Koves develops PCD grain sizes and binder phases in-house, so a grade can be matched to your alloy and operation instead of forcing your process onto a standard grade.
Frequently asked questions
Can PCD be used on steel or cast iron?
How long does a PCD edge last compared with carbide?
Send us your workpiece material, hardness and machine parameters. Our engineers will recommend the right grade and cutting data.