Tungsten Carbide End Mill Selection: The Decisive Influence of Grade, Coating, and Number of Cutting

1. What is a tungsten carbide end mill?

Tungsten carbide end mills (solid carbide end mills) are made from tungsten carbide powder and cobalt binder through pressing, sintering, and precision grinding. Their integral carbide structure gives them extremely high bending stiffness and wear resistance, making them widely used in high-speed machining and for cutting difficult-to-machine materials.

Core performance data:

Hardness: HRA 89–93

Flexural strength: 2500–3500 MPa

Heat resistance temperature: 800–1000°C (after coating)

Recommended cutting speed (for ordinary steel): 80–200 m/min, which is 3–5 times that of HSS end mills.

2. Grain size and grade selection

Common grain size (1.0–2.0 μm) : Used for rough machining, cast iron, and non-ferrous metals.

Fine grain (0.5–0.8 μm) : Tool life increased by 50–100%, suitable for stainless steel and titanium alloys.

Submicron/ultrafine grains (0.2–0.4 μm) : Used for hardened steel and graphite electrodes with HRC50 and above, producing extremely sharp cutting edges.

Effect of cobalt content :

6% cobalt content: high hardness, suitable for precision machining.

10% cobalt content: good toughness, suitable for interrupted cutting.

Cobalt content 12%–15%: Impact resistant, suitable for heavy-duty roughing.

3. Matching coatings and workpiece materials

4. The logic of selecting the number of flutes

2 flutes: Large chip flute, but low rigidity. Used for: slotting and roughing of soft materials like aluminum and plastic.

3 flutes: A balance between chip removal and rigidity. Used for: roughing of non-ferrous metals and stainless steel.

4 flutes: High rigidity, but small chip space. Used for: finishing of general steel and alloy steel, and high-feed milling.

6 flutes or more: Extremely high rigidity. Used for: precision finishing of high-hardness materials.

Conclusion

The performance of a tungsten carbide end mill does not depend solely on its price, but on whether its parameters (grade, coating, geometry) are perfectly matched to your specific machining task. WAT Cutting Tools offers professional customized solutions to ensure you find the most cost-effective tool for your milling challenges.