Fatigue Failure in Titanium Components
S-N curves, fatigue life prediction, surface treatments.
Quick Answer
Fatigue initiates at stress concentrations under cyclic loading. Titanium has a fatigue limit like steel.
Fatigue Limits @ 10^7 cycles
| Alloy | Limit (ksi) |
|---|---|
| Ti-6Al-4V Annealed | 65-75 |
| Ti-6Al-4V STA | 75-90 |
| Ti-6Al-4V ELI | 60-75 |
Surface Treatment Effects
- Shot peening: +20-40% life
- Polishing: +15-25%
- Anodizing: -10-20%
References
- ASTM E466, ASTM F2066