Description
- Titanium Grade 5-ELI –
- Ti6Al4V
- ELI
- Material number: 3.7165 (DIN)
- ISO 5832-3/ASTM F 136
Description
Titanium Grade 5-ELI (Extra Low Interstitial elements) is a variant of Grade 5. This variant of the titanium alloy has a higher purity (than “normal” Grade 5), and is mainly used in medical technology, surgical implants and dental prosthetics. The alloy is used in the aforementioned applications because it is best accepted by the human body.
However, the higher purity of Grade 5-ELI compared to Grade 5 is associated with slightly poorer mechanical properties. At the same time, however, the speed of the corrosion-induced crack growth is significantly reduced.
Indication
Titanium Grade 5 ELI can be used to manufacture crowns and bridges in the anterior and posterior tooth area. Bridge substructures for the anterior teeth may be produced with up to 3 contiguous pontics. The connector cross-section must not be less than 6 mm². In the posterior tooth area, bridges may not contain more than 3 contiguous pontics. A connector cross-section of at least 9 mm² is recommended. Furthermore, bars, implant bridges and superstructure can be produced.
Veneering
Titanium framework can be veneered with a veneering ceramic suitable for titanium. Observe the operating instructions of the applicable manufacturer.
Finishing/cleaning
The substructures can be finished using a clean, titanium-suitable carbide cutter. To do this, the tools must only be pulled over the surface in one direction in order to avoid material overlaps and possible bubble formation during ceramic veneering. In addition, the maximum speeds of the instruments recommended by the manufacturer must be observed. Subsequently, pure aluminium oxide (approx. 180 μm) should be used to sand the surfaces, using a pressure of 2–3 bar. Afterwards, thoroughly rinse the substructure under running water, or evaporate with hot steam and degrease with ethyl alcohol. Never use hydrofluoric acid!
Chemical composition
| Chemical composition | |||||||
|---|---|---|---|---|---|---|---|
| Fe (in %) | C (in %) | N (in %) | O (in %) | H (in %) | Al (in %) | V (in %) | Ti (in %) |
| ≤ 0.25 | ≤ 0.08 | ≤ 0.05 | ≤ 0.13 | ≤ 0.012 | 5.50 – 6.50 | 3.50 – 4.50 | Remainder |
Physical / Mechanical properties (guidelines)
| Physical / mechanical properties (guidelines) | ||
|---|---|---|
| Value | Unit | |
| Coefficient of thermal expansion (20–100°C) | 9.0 | [10⁻⁶ K⁻¹] |
| Specific heat capacity (ambient) | 526 | [J•kg⁻¹•K⁻¹] |
| Thermal conductivity (ambient) | 6.6 | [W•m⁻¹•K⁻¹] |
| Specific electrical resistance (ambient) | 1.7 | [Ω•mm²•m⁻¹] |
| Density (20°C) | 4.42 | [g/cm³] |
| Elasticity modulus (20°C) | 114,000 | [MPa] |
Tensile test at room temperature (guidelines)
| Tensile test at room temperature (guidelines) | ||
|---|---|---|
| Range | Unit | |
| Elastic limit Rₚ0.2 (min./max.) | 815 – 860 | [MPa] |
| Tensile strength Rₘ (min./max.) | 1085 – 1153 | [MPa] |
| Elongation at break A (min./max.) | 13 – 15 | [%] |
| Contraction at fracture Z (min./max.) | 42 – 44 | [%] |
Thermal properties
| Thermal properties | ||
|---|---|---|
| Value | Unit | |
| Temperature — low stress annealing | ca. 500 – 650 | [°C] / 932–1202 °F |
| Temperature — recrystallizing annealing | approx. 730 | [°C] / 1346 °F |