What is TA5 titanium and it's difference with TC4?
What are the differences between TA4 commercially pure titanium and TA5 near-alpha titanium alloy—and how do we choose between them? Let us explore their composition, properties and application together, to find out the differences.
TA4 and TA5 Chemical composition comparison
| Item | TA4 (Commercially Pure Titanium) | TA5 (Near-Alpha Titanium Alloy) |
|---|---|---|
| Ti | Balance (≥ 98.5%) | Balance |
| Al | — | ~ 4.5–6.5% |
| V | — | — |
| Fe | ≤ 0.50% | ≤ 0.30% (depending on specification) |
| O | ≤ 0.40% | ≤ 0.15–0.20% |
| C | ≤ 0.08% | ≤ 0.10% |
| N | ≤ 0.05% | ≤ 0.05% |
| H | ≤ 0.015% | ≤ 0.015% |
| Material Type | Commercially Pure Titanium (α) | Near-Alpha Titanium Alloy |
Mechanical properties TA4 vs TA5
| Item | TA4 | TA5 |
|---|---|---|
| Tensile Strength (MPa) | ~ 550–750 | ~ 700–900 |
| Yield Strength (MPa) | ~ 480–600 | ~ 600–750 |
| Elongation (%) | ≥ 15% | 8–15% |
| Elastic Modulus (GPa) | ~ 105 | ~ 110 |
| Hardness (HB) | 150–200 | 200–260 |
| Strengthening Mechanism | Oxygen solid-solution strengthening | Alloying strengthening (mainly Al) |
Physical properties difference between TA4 and TA5
| Item | TA4 | TA5 |
|---|---|---|
| Density (g/cm³) | ~ 4.51 | ~ 4.50–4.52 |
| Melting Point (°C) | ~ 1660 | ~ 1660 |
| Thermal Conductivity (W/m·K) | ~ 16–18 | ~ 6–8 |
| Electrical Resistivity (μΩ·m) | ~ 0.42 | ~ 0.55 |
| α-Phase Content | 100% (single α phase) | Near-α (~90% α phase) |
| High-Temperature Stability | Good | Better |
| Corrosion Resistance | Excellent | Excellent |
Corrosion Resistance
TA4, as a commercially pure titanium, offers excellent corrosion resistance thanks to its high titanium content and stable oxide film. It performs especially well in seawater, chloride environments, and most chemical media.
TA5 also has strong corrosion resistance, but because it contains aluminum as an alloying element, its corrosion performance is slightly more dependent on the service environment. In general, TA4 has a slight edge in aggressive corrosive conditions, while TA5 still maintains very good resistance suitable for most engineering uses.
Heat Treatment and Processing
TA4 cannot be significantly strengthened through heat treatment because it is a single-phase α titanium material; its strength mainly comes from oxygen content. It is typically processed through hot working, and its cold formability is moderate.
TA5, as a near-alpha alloy, responds better to heat treatment and can achieve higher strength through specific thermal processing routes. However, it is generally harder to deform than TA4, especially in cold-working conditions, and may require more controlled processing parameters.
Weldability
TA4 has very good weldability and is often preferred when clean, reliable welds are required. Its simple composition allows stable weld quality without significant risk of embrittlement.
TA5 is also weldable, but because it contains aluminum and has higher strength, it requires tighter control of shielding gas, heat input, and post-weld handling. Improper welding may lead to reduced ductility in the heat-affected zone, making TA4 the more forgiving option for welding operations.
Shared applications of TA4 & TA5
Both TA4 and TA5 are widely used in industries where corrosion resistance, lightweight characteristics, and reliability are essential. Their overlapping applications mainly include:
Chemical processing equipment: reaction vessels, piping, pumps, and valves exposed to corrosive media.
Marine engineering: seawater heat exchangers, condenser tubing, offshore structures, and components that require long-term corrosion resistance.
Heat exchange systems: plates, tubes, and frames used in industrial heat exchangers under moderate mechanical loads.
Aerospace non-critical structures: brackets, housings, access panels, and fairing elements where corrosion resistance, weldability, and weight reduction are important.
Featured applications of TA4 (commercially pure titanium)
TA4 excels in fields where biocompatibility, formability, and maximum corrosion resistance dominate the design criteria. Its unique applications include:
Medical implants and devices: orthopedic plates, screws, dental implants, and surgical instruments.
Electrochemical systems: electrolytic cell components, anodes, and electroplating equipment.
Ultra-corrosive environments: chlorine processing lines, bromine handling systems, and acid storage tanks.
Industrial components requiring clean welds: welded structures, thin-wall tubes, and chemical tubing where welding reliability is critical.
TA4 is preferred when purity, corrosion resistance, and weldability outweigh the need for high mechanical strength.
Featured applications of TA5 (near-alpha titanium alloy)
TA5 is chosen for applications demanding higher strength, better high-temperature performance, and improved fatigue resistance. Its unique application areas include:
Aerospace structural parts: high-strength fittings, load-bearing brackets, landing gear components, and structural reinforcements.
Aerospace engine zones: compressor components, casings, and parts operating at elevated temperatures.
High-pressure systems: pressure vessels, chemical reactors, and heavy-duty pipeline systems.
High-performance consumer and industrial products: premium bicycle frames, racing components, high-strength sports equipment, and lightweight precision machined parts.
TA5 bridges the gap between corrosion resistance and structural strength, making it suited for more demanding mechanical environments than TA4.
At Shenzhen Chinalco Metal, we offer a wide range of TA4 (commercially pure titanium) and TA5 (near-alpha titanium alloy) products, including
Titanium plates / sheets：AMS4901 TA4 plate
Titanium bars
Titanium tubes
Titanium wires
Titanium foils: ASTM B265 aircraft foil
All these forms can be customized according to customer requirements, serving a variety of applications such as chemical equipment, marine heat exchangers, and aerospace components.