AMS 4956 aerospace Gr5 ELI titanium wire Description
Product Introduction
AMS 4956 Gr5 ELI aerospace titanium wire (Ti-6Al-4V ELI/UNS R56401) is an extra-low-interstitial titanium alloy welding wire conforming to AMS 4956 for aerospace TIG welding. The specification is purpose-built for welding fracture-critical aerospace structures. Tight limits on oxygen (≤0.13%) and iron (≤0.25%) substantially improve weld fracture toughness and cryogenic ductility. Used for welding damage-tolerant airframe structures, cryogenic plumbing, and fracture-critical components. Available from φ0.5 mm to φ4.0 mm, as straight wire or precision layer-wound coil.
Technical Specifications
1. Basic Information
Product Name | AMS 4956 aerospace Gr5 ELI titanium wire |
Grade Equivalents | AMS 4956/ASTM Gr5 ELI/UNS R56401/Ti-6Al-4V ELI |
Standards | AMS 4956, ASTM B863, AWS A5.16 (ERTi-5 ELI) |
Supply Forms | Straight wire, Precision layer-wound coil |
Surface Conditions | Bright finish, Cleaned |
Diameter Range | φ0.5–φ4.0 mm |
Straightness | ≤ 2/1000 |
2. Chemical Compositions
Ti | Al | V | Fe | O | C | N | H | Y | Total Others |
Balance | 5.50-6.50% | 3.50-4.50% | ≤0.25% | ≤0.13% | ≤0.08% | ≤0.05% | ≤0.012% | ≤0.005% | ≤0.40% |
3. Mechanical Properties
Tempers | UTS (MPa) | YS (MPa) | Elongations (%) |
Annealed | ≥860 | ≥795 | ≥10 |
4. Physical Properties
Properties | Values |
Density | 4.43 g/cm³ |
Melting Point | ≈1649°C |
Elastic Modulus | 110 GPa |
Coefficient of Thermal Expansion | 8.6×10⁻⁶/°C |
Thermal Conductivity | 6.7 W/(m·K) |
Magnetic Properties | Non-magnetic |
Max. Service Temperature | ≤350°C continuous |
Cryogenic Limit | No embrittlement below -196°C |
Features and Advantages
- AMS 4956 certified: Purpose-built for aerospace fracture-critical structure welding; meets damage-tolerant design requirements.
- High fracture toughness: ELI-grade interstitial control delivers significantly higher weld KIC values and fatigue crack growth resistance than standard Gr5.
- Cryogenic reliability: Retains ductility below -196°C; the standard material for LOX and LH₂ propulsion line welding.
- Reliable deposited weld: Weld metal UTS ≥860 MPa, fully matching Gr5 ELI parent metal properties.
- Precision layer-wound: Uniform feed tension, smooth feeding; compatible with automated aerospace TIG welding systems.
- Full lot traceability: Complete test reports and material certificates per lot, meeting FAR/CS airworthiness requirements.
Performance Solutions
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A. Problem: Standard Gr5 welding wire produces deposited welds with low fracture toughness, making fracture-critical aerospace weldments unreliable.
Solution: AMS 4956 aerospace Gr5 ELI titanium wire delivers significantly higher weld KIC values, meeting damage-tolerant design requirements for fracture-critical aerospace structures.
B. Problem: Aerospace cryogenic line welds fail by brittle fracture in LOX/LH₂ service, creating critical safety hazards.
Solution: AMS 4956 aerospace Gr5 ELI titanium wires do not embrittle below -196°C. The standard welding material for spacecraft cryogenic propellant plumbing.
C. Problem: Conventional wire with high lot-to-lot variation forces frequent adjustment of aerospace welding parameters.
Solution: AMS 4956 aerospace Gr5 ELI titanium wire delivers highly consistent lot-to-lot performance. Stable process window. Reproducible weld quality.
D. Problem: Surface contamination on welding wire causes micro-cracks in aerospace welds, with fatigue life far below design targets.
Solution: AMS 4956 aerospace Gr5 ELI titanium wire undergoes rigorous cleaning and sealed packaging. Contamination-free surface. Minimum micro-crack risk.
Applications
1. Aerospace Fracture-Critical Structural Welding
TIG welding of wing spars, fuselage frames, landing gear struts, and engine pylons—all fracture-critical components. Meets damage-tolerant design requirements. FAA/EASA airworthiness certified.
2. Spacecraft Cryogenic Propulsion System Welding
Welding of LOX/LH₂ propellant lines, cryogenic valves, and tank support structures. Retains toughness below -196°C. Critical welding material for spacecraft cryogenic systems.
3. Aero Engine Fracture-Critical Component Welding
Repair welding of engine fan disks, compressor rotors, and turbine cases. High fracture toughness meets engine airworthiness requirements.
4. Aircraft Hydraulic and Pneumatic High-Pressure Systems
Welding of high-pressure hydraulic lines, pneumatic ducts, and titanium pressure vessels. Pressure-tight with fatigue resistance. Meets 5,000 psi+ system requirements.
5. Titanium alloy welding of satellite load-bearing frames, rocket interstages, and spacecraft docking mechanisms. High reliability with excellent airworthiness and launch certification acceptance rates.