Titanium Grade 5, also known as Ti‑6Al‑4V, is an alpha‑beta titanium alloy standardized under specifications such as ASTM Grade 5 and UNS R56400. It combines very high tensile and yield strength with low density around 4.43 g/cm³, excellent corrosion resistance, and stable behavior up to service temperatures near 400 °C. The alloy exhibits good fatigue strength and weldability, while its machinability requires controlled parameters to manage heat and tool wear and to achieve consistent material properties and tolerances. Typical product forms include bar, plate, sheet, forgings, and tubing used in aerospace fasteners, turbine and airframe parts, medical implants, and other high-performance structural components. In CNC machining, Titanium Grade 5 is selected where a combination of high strength, fatigue performance, and tight tolerances is required in weight‑sensitive aerospace, medical, and industrial parts.
Properties of Titanium Grade 5
| Ultimate tensile strength (MPa) | 920-1000 |
| Yield strength (MPa) | 830-880 |
| Young's modulus (modulus of elasticity) (GPa) | 113.8 |
| Elongation at break(%) | 9-11 |
| Fatigue Strength (MPa) | 240 |
| Hardness (Brinell) | 330-340 HB |
| Density (g/cm³) | 4.43 |
| Corrosion resistance | Excellent |
| Weldability | Good |
| Maximum service temperature(°C) | 400-500 |
| Thermal expansion coefficent (10-6/ºC) | 8.6-9 |
| Thermal conductivity (W/(m⋅°C)) | 6.7-7.2 |
| Electrical resistivity (μΩ.cm) | 170-180 |
| Post-Processing | Annealing & Cold working |
| Anodizing compatibility | Suitable |
| Magnetism | Non-magnetic |
CNC machining Titanium Grade 5
Titanium Grade 5 is significantly stronger and more challenging to machine than commercially pure grades, requiring tightly controlled CNC machining parameters. Lower cutting speeds, appropriate feed rates, sharp carbide tools, and high‑pressure coolant are important to manage heat, prevent work‑hardening, and limit tool wear. Stable tool engagement and rigid fixturing are critical for thin‑walled, pocketed, or complex geometries, helping maintain dimensional accuracy and surface integrity on critical aerospace, medical, and industrial components. For very tight tolerances or demanding surface finish requirements, optimised toolpaths and, where necessary, secondary finishing or polishing steps are often used to achieve the desired result.
Available Finishes
For Titanium Grade 5 components, finishing processes help refine surface integrity to support fatigue resistance, corrosion performance, and cleanliness in demanding service conditions. Control of surface roughness and near‑surface microstructure contributes to dimensional stability at sealing faces, bearing interfaces, and load‑bearing joints. When applied to Titanium Grade 5 CNC machining parts, these treatments can reduce tool-mark-induced stress concentrations and prepare the material for any subsequent coating or functional use. For medical and high‑purity applications, surface preparation and finishing also support cleanability, reduced contamination risk, and stable long‑term biocompatible performance where required. Anodizing (Type II and Type III) is commonly applied to Titanium Grade 5 to improve wear behaviour, adjust friction, and provide colour‑coded identification for fasteners and critical components.
| As machined (Standard) | Passivation |
| As machined (Medium) | Sand blasting |
| As machined (Fine) | Media blasting |
| Brushed finish | Chromate conversion coating |
| Electropolishing | Anodizing Type II |
| Hand polishing | Anodizing Type III |
| Polishing | |
| Bead blasting | |
| Powder coating |
Frequently Asked Questions
What are the typical mechanical properties of Titanium Grade 5?
Titanium Grade 5 typically exhibits ultimate tensile strength around 920–1000 MPa and yield strength in the range of 830–880 MPa, depending on product form and heat treatment. Elongation at break is commonly about 9–11%, with a modulus of elasticity near 113–114 GPa, giving the alloy a high strength‑to‑weight ratio suitable for highly loaded but weight‑sensitive components.
How does Titanium Grade 5 perform at elevated temperatures and in aggressive environments?
Titanium Grade 5 retains useful for continuous service up to around 400 °C, with good creep resistance at intermediate temperatures when used within design stress limits. Its stable oxide film provides excellent corrosion resistance in many chloride-containing, oxidizing, and mildly reducing media, supporting long-term use in aerospace, offshore, and chemical processing environments.
What should engineers consider regarding machinability and design features when using Titanium Grade 5?
Titanium Grade 5 has more challenging machinability than commercially pure grades, benefiting from lower cutting speeds, high-pressure coolant, and rigid setups to control heat and tool wear. From a design perspective, avoiding abrupt section changes, providing adequate radii, and allowing reasonable machining allowances and tolerances can help achieve consistent dimensional accuracy and surface quality across complex geometries.