Titanium Grade 5 ELI (Grade 23)

Titanium Grade 5 ELI (Extra Low Interstitials)also known as Grade 23, is a specialized version of the well-known Ti6Al4V titanium alloy, characterized by exceptionally low levels of interstitial elements. This results in even higher strength and improved weldability. These properties make Titanium Grade 5 ELI the preferred choice for high-load applications requiring extreme strength, corrosion resistance, and long-term durability. It is commonly used in the medical, aerospace, and high-tech industries, where top-level mechanical properties and reliability are essential.

Due to its superior mechanical properties, Titanium Grade 5 ELI is particularly well suited for structural components exposed to high stress. It offers excellent corrosion resistance and is extremely resistant to material fatigue and crack formation. The reduced content of interstitial elements also improves hardness and formability, which is advantageous for precision manufacturing processes in demanding applications. Titanium Grade 5 ELI is often used in environments requiring exceptional strength, reliability, and longevity.

This material demonstrates particularly high resistance in seawater and marine environments. However, it is most commonly found in the medical sector, especially in implants and surgical devices, where the strictest standards must be met. For medical applications, the very high biocompatibility and the absence of toxic or allergenic components in Titanium Grade 5 ELI are especially noteworthy. Its high biocompatibility ensures excellent acceptance by the human body—one of the key reasons why it is so frequently used in medical technology.

Applications include:

• Medical implants such as bone prostheses and hip implants
• Medical devices, cryogenic equipment, and ultrasonic technology
• Everyday products such as watch components and jewelry
• Fasteners and clamping elements in industrial technology
• High-load components in the aerospace industry, such as engine parts and landing gear structures

Physical Properties:

• Density: 4,47 g/cm³
• Specific Heat: 0,56 J/(g·K)
• Thermal Conductivity: 6,6 W/(m·K)
• Modulus of Elasticity: 114 (KN/mm²)
• Electrical Resistivity: 1,71 Ω·mm²/m
• Thermal Expansion: 8,9·10⁻⁶/K
• Beta-Transus Temperature: 977 °C

Mechanical Properties:

• Tensile Strength: 828 MPa min.
• Yield Strength: 759 MPa
• Elongation: 10% min.
• Constriction: 15% min.

Heat Treatments:

• Annealing (Soft Annealing): 700 – 840 °C
• Stress Relief Annealing: 550 – 700 °C

The heat treatment of Grade 5 titanium requires a protective gas atmosphere or a vacuum environment due to titanium’s high affinity for oxygen, which can make the material brittle.

Welding Methods:

MIG (Metal Inert Gas)
TIG (Tungsten Inert Gas)
Argon shielding gas welding
Plasma welding
Laser welding
Electron beam welding