The most widely used titanium grade is Ti-6Al-4V, Grade 5 alloy (UNS R56400), also known as TC4. This two-phase α+β titanium alloy includes aluminum as the alpha stabilizer and vanadium as the beta stabilizer. Its high-strength properties allow for use at cryogenic temperatures up to approximately 800°F (427°C) and is typically used in the annealed condition.
Similar to other titanium alloys, Ti 64 alloy’s corrosion resistance is due to the formation of a consistent and continuous oxide layer, which forms spontaneously upon exposure to oxygen. This makes it an excellent option for seawater corrosion resistance, making it a preferred choice for offshore and subsea oil & gas operations.
Although Ti-6Al-4V is resistant to general corrosion, it can be quickly attacked by environments that cause breakdown of the protective oxide layer, such as hydrofluoric (HF), hydrochloric (HCl), sulfuric, and phosphoric acids. However, it can resist attack by pure hydrocarbons and most chlorinated and fluorinated hydrocarbons, provided that water has not caused the formation of small amounts of hydrochloric and hydrofluoric acids.
Production of Ti-6Al-4V alloy is achieved through primary melting using vacuum arc (VAR), electron beam (EB), or plasma arc hearth melting (PAM). To refine the alloy, vacuum arc remelting is used. Ti-6Al-4V has a modulus of elasticity of 107 Gpa (16.5 x 103 ksi), which is roughly half that of carbon steels, like other titanium alloys.
Similar to other titanium alloys, Ti 64 alloy’s corrosion resistance is due to the formation of a consistent and continuous oxide layer, which forms spontaneously upon exposure to oxygen. This makes it an excellent option for seawater corrosion resistance, making it a preferred choice for offshore and subsea oil & gas operations.
Although Ti-6Al-4V is resistant to general corrosion, it can be quickly attacked by environments that cause breakdown of the protective oxide layer, such as hydrofluoric (HF), hydrochloric (HCl), sulfuric, and phosphoric acids. However, it can resist attack by pure hydrocarbons and most chlorinated and fluorinated hydrocarbons, provided that water has not caused the formation of small amounts of hydrochloric and hydrofluoric acids.
Production of Ti-6Al-4V alloy is achieved through primary melting using vacuum arc (VAR), electron beam (EB), or plasma arc hearth melting (PAM). To refine the alloy, vacuum arc remelting is used. Ti-6Al-4V has a modulus of elasticity of 107 Gpa (16.5 x 103 ksi), which is roughly half that of carbon steels, like other titanium alloys.
Why We Use Ti-6Al-4V
The combination of high strength, corrosion resistance, biocompatibility, low thermal expansion, good weldability, and high fatigue resistance makes Ti-6Al-4V a popular choice for many industrial and biomedical applications. Ti-6Al-4V has several advantages due to its unique composition and properties, some of which are:
- High Strength: Ti-6Al-4V is a high-strength titanium alloy that provides excellent strength-to-weight ratio, making it an ideal choice for many aerospace and industrial applications.
- Corrosion Resistance: This alloy has excellent corrosion resistance, particularly in seawater and chloride-containing environments, due to the formation of a protective oxide layer on its surface.
- Biocompatibility: Ti-6Al-4V is biocompatible and non-toxic, making it suitable for use in medical implants, such as dental implants, artificial joints, and other surgical implants.
- Low Thermal Expansion: This alloy has a low coefficient of thermal expansion, which means that it expands and contracts less than other metal alloys when exposed to extreme temperature changes, making it ideal for high-temperature applications.
- Good Weldability: Ti-6Al-4V can be easily welded using different processes, including gas tungsten arc welding (GTAW), electron beam welding (EBW), and laser beam welding (LBW).
- Excellent Fatigue Resistance: This alloy has high fatigue resistance, which means that it can withstand repeated stress and loading cycles without failure, making it suitable for many critical components in aerospace and automotive industries.
Ti-6Al-4V Application
The combination of high strength, low weight, biocompatibility, and excellent corrosion resistance makes Ti-6Al-4V an ideal choice for use in various industries, ranging from aerospace and biomedical to automotive and chemical processing.Ti-6Al-4V alloy is widely used in various applications due to its unique properties. Some of the most common applications are:
- Aerospace and Aviation: Ti-6Al-4V is extensively used in the aerospace and aviation industries, where high strength, low weight, and corrosion resistance are essential for components such as aircraft frames, jet engines, landing gear, and other critical components.
- Biomedical Implants: Due to its biocompatibility, Ti-6Al-4V is commonly used in biomedical implants, including dental implants, artificial joints, and bone plates.
- Marine Engineering: This alloy is an ideal choice for marine engineering applications due to its excellent corrosion resistance in seawater. It is used in offshore platforms, underwater pipelines, and subsea connectors.
- Automotive Industry: Ti-6Al-4V is used in the automotive industry in various parts, including exhaust systems, suspension components, and engine valves, due to its high strength-to-weight ratio.
- Sporting Goods: This alloy is utilized in various sporting goods, including golf clubs, bicycle frames, and tennis rackets, due to its lightweight, high strength, and resistance to fatigue.
- Chemical Processing: Ti-6Al-4V is used in chemical processing applications, such as heat exchangers, valves, and pumps, due to its resistance to corrosive environments and excellent thermal properties.
Characteristic Of Ti-6Al-4V
Density | Modulus (GPa) | Shear Modulus(GPa) | Bulk Modulus(GPA) | Press Strength (Mpa) | Pulling Strength (Mpa) | HRC |
4.4 | 110 | 42 | 97-150 | 900 | 920-950 | 32-36 |
