Exceptional Strength-to-Weight Ratio • Biocompatible • Corrosion Resistant
Ti-6Al-4V, also known as Grade 5 titanium, is the most widely used titanium alloy in the world. Combining outstanding strength with extremely low density (45% lighter than steel), superior corrosion resistance, and biocompatibility, it's the material of choice for aerospace structures, medical implants, and high-performance applications where weight reduction is critical.
Ti-6Al-4V is an alpha-beta titanium alloy containing 6% aluminum (alpha stabilizer) and 4% vanadium (beta stabilizer). This dual-phase microstructure provides an exceptional combination of strength, low weight, and toughness that makes it the workhorse of the titanium industry. With only 56% the density of steel but comparable strength, it delivers the highest strength-to-weight ratio of any metallic structural material.
At just 4.43 g/cm³, Ti-6Al-4V weighs 45% less than steel and 60% more than aluminum, yet delivers strength approaching that of high-strength steels. This unique combination enables dramatic weight reduction in aerospace structures, medical devices, and performance applications where every gram matters. A component made from Ti-6Al-4V can weigh half that of an equivalent steel part while maintaining comparable strength.
| Element | Weight % | Purpose |
|---|---|---|
| Titanium (Ti) | Balance (≈90%) | Base metal, provides corrosion resistance and biocompatibility |
| Aluminum (Al) | 5.5 - 6.75 | Alpha stabilizer, reduces density, increases strength |
| Vanadium (V) | 3.5 - 4.5 | Beta stabilizer, improves ductility and formability |
| Iron (Fe) | ≤ 0.30 | Beta stabilizer, increases strength (impurity limit) |
| Oxygen (O) | ≤ 0.20 | Interstitial strengthener (controlled impurity) |
| Carbon (C) | ≤ 0.08 | Strengthening element (impurity limit) |
| Nitrogen (N) | ≤ 0.05 | Strengthening element (impurity limit) |
| Hydrogen (H) | ≤ 0.015 | Must be minimized (causes embrittlement) |
| Other Elements | ≤ 0.40 total | Residual elements (each ≤0.10%) |
Alpha-Beta Microstructure: The 6% aluminum stabilizes the alpha (HCP) phase, while 4% vanadium stabilizes the beta (BCC) phase. This creates a dual-phase microstructure that combines the strength of alpha with the ductility of beta, resulting in superior mechanical properties.
| Property | Metric | Imperial |
|---|---|---|
| Tensile Strength (Ultimate) | 950 MPa | 138,000 psi |
| Yield Strength (0.2% offset) | 880 MPa | 128,000 psi |
| Elongation at Break | 10% (in 50mm) - Sheet/Plate | |
| Reduction of Area | 25% minimum | |
| Modulus of Elasticity | 114 GPa | 16.5 × 10⁶ psi |
| Rockwell Hardness | 36 HRC (typical) | |
| Brinell Hardness | 334 HB | |
| Shear Strength | 550 MPa | 80,000 psi |
| Shear Modulus | 44 GPa | 6.4 × 10⁶ psi |
| Fatigue Strength (10⁷ cycles) | 510 MPa | 74,000 psi |
Note: Properties shown are for mill-annealed condition. Solution treated and aged (STA) condition can achieve tensile strengths exceeding 1100 MPa. Medical grade (ASTM F136) has tighter specifications for improved biocompatibility.
Aircraft structural components, landing gear, wing spars, fuselage frames, fasteners, hydraulic tubing, engine components (compressor blades, discs, casings), rocket motor cases, spacecraft structures, and critical airframe parts where weight reduction is essential.
Orthopedic implants (hip and knee replacements, bone plates, screws), dental implants, surgical instruments, pacemaker cases, artificial heart valves, spinal fusion cages, and prosthetic devices. Grade 23 (Ti-6Al-4V ELI) specifically for surgical implants.
High-performance connecting rods, valves, valve springs, turbocharger components, exhaust systems, suspension components, racing car chassis parts, Formula 1 components, and performance vehicle parts where weight reduction improves performance.
Propeller shafts, boat rigging, underwater vehicle components, submarine pressure hulls, naval ship components, offshore oil platform equipment, desalination plant components, and seawater-resistant hardware.
Reaction vessels, heat exchangers, pumps, valves, process piping in corrosive service, chemical plant equipment, and components requiring both corrosion resistance and strength.
High-end bicycle frames, golf club heads, tennis racquets, climbing equipment, diving equipment, firearms components, and premium sporting goods where performance justifies the material cost.
| Operation | Recommended Parameters |
|---|---|
| Turning (Roughing) | Speed: 60-80 SFM (18-24 m/min), Feed: 0.010-0.020 ipr, DOC: 0.100-0.200" |
| Turning (Finishing) | Speed: 80-120 SFM (24-37 m/min), Feed: 0.005-0.010 ipr |
| Milling (Carbide) | Speed: 100-150 SFM (30-46 m/min), Heavy feeds, climb milling preferred |
| Drilling | Speed: 20-40 SFM (6-12 m/min), Peck drilling mandatory, use through-tool coolant |
| Threading | Very low speeds, thread milling preferred, form taps can work with care |
| Coolant | HIGH-PRESSURE flood coolant MANDATORY - water-soluble or chlorinated oils |
Critical Success Factor: The key to machining titanium is SLOW speeds with HEAVY feeds and continuous sharp cutting action. Never let the tool rub or dwell. The low thermal conductivity means all heat stays at the cutting edge, so abundant coolant is essential. Use the sharpest tools available and replace them before they dull.
Ti-6Al-4V can be welded successfully, but titanium's extreme reactivity with atmospheric gases (oxygen, nitrogen, hydrogen) at elevated temperatures requires special precautions. Contamination from air exposure during welding causes embrittlement and strength loss.
Weld color indicates contamination level:
Ti-6Al-4V forms a stable, protective titanium dioxide (TiO₂) passive film that provides exceptional corrosion resistance in most environments. This passive layer reforms instantly if damaged, providing superior protection compared to stainless steels.
Ti-6Al-4V significantly outperforms 316 stainless steel in seawater, chloride environments, and oxidizing acids. The passive film is more stable and resistant to breakdown, making titanium immune to pitting and crevice corrosion in environments that would attack stainless steels.
Get a quote for AS9100D certified Ti-6Al-4V titanium machining with full material traceability and aerospace certification.