Zhuzhou Aite Cemented Carbide Co., Ltd
How Cemented Carbide (Tungsten-Carbide) Is Made ？
How Cemented Carbide (Tungsten-Carbide) Is Made ？
1. Start with the powders
• Tungsten carbide (WC): Tungsten ore reacts with carbon at 1 400–1 600 °C to form hard WC grains, which are then ball-milled into micron-sized powder.
• Cobalt (Co): acts as the metallic “glue,” typically 5–15 %.
• High-temperature sinter: 1350–1450 °C in vacuum or hydrogen. The cobalt melts, flows between WC grains, and pulls them together by capillary action. On cooling, the cobalt solidifies and locks the grains in a dense, pore-free body (relative density > 99 %).
• Precision grinding: Only diamond wheels can cut the fully sintered carbide.
• Coatings: Chemical or physical vapor deposition (TiN, TiAlN, Al₂O₃) triple tool life.
• Cobalt (Co): acts as the metallic “glue,” typically 5–15 %.
2. Mix & wet-grind
The powders are charged into ball mills with alcohol or hexane and ground for 24–72 h. A little wax or PEG is added so the mix will press like clay.3. Press into “green” parts
The damp powder is compacted in steel dies or by cold isostatic pressing (200–400 MPa). The part is now strong enough to handle but still full of pores.4. Sinter (the magic step)
• Pre-sinter: 400–600 °C in a low-oxygen furnace to vaporize the wax.• High-temperature sinter: 1350–1450 °C in vacuum or hydrogen. The cobalt melts, flows between WC grains, and pulls them together by capillary action. On cooling, the cobalt solidifies and locks the grains in a dense, pore-free body (relative density > 99 %).
5. Post-sinter finishing
• Hot isostatic pressing (HIP) may follow for aerospace grades—this squeezes out any last micro-voids.• Precision grinding: Only diamond wheels can cut the fully sintered carbide.
• Coatings: Chemical or physical vapor deposition (TiN, TiAlN, Al₂O₃) triple tool life.
