oron carbide (B₄C) is harder, lighter, and more brittle; tungsten carbide (WC) is tougher, denser, more wear-resistant in industrial use, and far more common.
1. Basic Properties
表格
| Property | Boron Carbide (B₄C) | Tungsten Carbide (WC) |
|---|---|---|
| Formula | B₄C | WC |
| Type | Ceramic | Cermet (ceramic-metal composite) |
| Density | ~2.52 g/cm³ (very light) | ~15.6 g/cm³ (very heavy) |
| Mohs Hardness | 9.5–9.75 (3rd hardest known) | 9.0–9.5 |
| Vickers Hardness | 30–38 GPa | 2,400–2,600 HV (~24–26 GPa) |
| Toughness | Low (brittle) | High (tough, shock-resistant) |
| Melting Point | ~2,450 °C | ~2,870 °C |
| Cost | High (specialized) | Moderate (mass-produced) |
2. Key Differences
- Hardness & Brittleness
- B₄C: Harder than WC but very brittle. It resists scratching but can chip or shatter under impact or bending.
- WC: Slightly softer but far tougher. It withstands shock, vibration, and heavy industrial impact without breaking.
- Weight
- B₄C: ~6× lighter than WC. Critical for portable/armor applications.
- WC: Very dense. Adds weight but improves penetration resistance (e.g., penetrators).
- Wear Mode
- B₄C: Excels at abrasion/grinding (hard particles) but fails under heavy impact.
- WC: Excels at continuous sliding/abrasive wear under load (ideal for tools).
3. Typical Applications
Boron Carbide (B₄C)
- Ballistic armor: Body armor, tank armor, helicopter panels (lightweight + high hardness).
- Abrasives / Blasting: Nozzles, water-jet cutters, grinding media for super-hard materials.
- Nuclear: Neutron absorber (control rods, shielding).
- High-end polishing: For gemstones, ceramics, and carbide.
Tungsten Carbide (WC)
- Cutting tools: Inserts, drills, end mills, saws (machining steel, cast iron, wood).
- Wear parts: Bearings, seals, dies, pump parts, mining tools.
- Ammunition: Kinetic energy penetrators (density + hardness).
- Jewelry / Watch cases: Scratch-resistant rings and watch parts.
4. Which to Choose?
- Choose Boron Carbide when you need:
- Maximum hardness
- Low weight (armor, portable parts)
- Neutron absorption (nuclear use)
- Abrasive grinding of hard materials
- Toughness & impact resistance
- Industrial wear resistance (sliding, grinding under load)
- High strength at temperature
- Cost-effective tooling (most common industrial choice)Choose Tungsten Carbide when you need:
In short: B₄C = hard & light (armor/abrasives); WC = tough & dense (industrial tools/wear parts).