The Science Behind Tungsten Carbide Grades
Not all tungsten carbide is created equal. The grade selection directly impacts blade life, cutting quality, and overall cost-per-part. Here's what every tobacco industry procurement professional should know.
Key Parameters
Hardness (HRA)
ZTLibre's standard HRA 89-92.5 range offers the optimal balance of wear resistance and toughness for tobacco cutting applications. Higher HRA (>93) provides extreme wear resistance but increases brittleness — unsuitable for impact-prone cutting operations.
Grain Size
- Sub-micron (0.2-0.5µm): Finest edge retention, ideal for precision cutting knives
- Medium (1-2µm): Best general-purpose for tobacco cutter blades
- Coarse (3-5µm): Maximum toughness for heavy-impact applications
Cobalt Content
Cobalt acts as the binder in tungsten carbide. Higher cobalt content (10-15%) increases toughness but reduces hardness. ZTLibre standard specification uses 6-10% cobalt binder for the optimal hardness-toughness balance.
Application-Specific Recommendations
| Application | HRA | Grain Size | Cobalt % |
|---|---|---|---|
| Tobacco cutter knives (Hauni KT2) | 91-92 | Sub-micron | 6% |
| Garniture tongue | 89-90 | Medium | 10% |
| Cut-off knives | 92-92.5 | Sub-micron | 6% |
| Tear tape knives | 90-91 | Medium | 8% |
Contact our technical team for custom carbide grade recommendations for your specific application.
