Titanium
- Too soft
- Too ductile >> more
Pure Titanium
Alloys of Titanium
- Lightweight
- Very stiff
- Exceptional strength-to-weight ratio
- Great reliability at high temperatures
- Very corrosion-resistant >> more
Shaped Memory Alloys
- Can be deformed but regains its original shape when heated above transition temperature
- Two phases:
- Martensite (below transition temperature) - can be deformed
- Austenite (above transition temperature) - undergoes strain and recovers original shape
Before: Shaped memory alloy after being deformed.
After: Above transition temperature.
The two possible phases of shaped memory alloys.
- Alloy of nickel and titanium in almost equal quantities
- Wire contracts in length but cross-section increases upon heating to keep volume constant
- Used in orthodontic archwires and prosthetic limbs >> more
NiTi wires for frames of spectacles and as Arch Wires
Roger Charter running with prosthetic legs, with the knees and ankles made of light titanium alloys.