Titanium Car Parts Guide: Grades, Manufacturing & Design

With the evolution of industries, research in materials has also increased to get more benefits and keep the costs low. In the Automotive industry, the main concerns are strength and fuel efficiency. Keeping both concerns at the high note, Titanium was introduced in the automotive industry in the late 1980s. Now, it is the primary choice and has replaced steel in many car parts. In this article, you will learn in which parts of high-performance racing cars Ti is used and why it is used.

What Is Titanium in Automotive Use?

In the automotive industry, Ti is considered one of the most expensive metals due to its excellent mechanical properties and is used in expensive cars only. In automotive use, Ti has great importance because it enhances the durability of a car.

What Cars Benefit Most from Titanium Parts?

These cars get most benefit from Ti metal:

High Performance Cars

High-performance cars offer power, fast speeds, and durability over normal cars. Ti is the metal that is used in the critical components of a high-performance car. It has a high strength-to-weight ratio and excellent corrosion resistance.

Racing Cars

Racing cars are the extreme version built only for racing. For instance, Formula 1, Le Mans, or GT racing, etc. In these, Ti plays a crucial role because of its lightweight and strength.

High Performance Motorcycles

High-performance motorcycles support power, speed, acceleration, and high strength. Ti is used in exhausts, valves, etc., in high-performance motorcycles.

Specific Racing Vehicles

Specific racing vehicles include Formula 1 cars and MotoGP bikes.

In Formula 1 cars, Ti is used in structural bolts.

In MotoGP bikes, Ti is used in the exhaust.

The Role of Titanium in Automotive Engineering

The role of Ti is:

• To provide automotive parts with high strength-to-weight ratios, excellent corrosion resistance
• To maintain the strength at high temperatures

Key Benefits of Using Titanium in Vehicles

Let's figure out the actual benefits of Ti in vehicles in this section.

Key Material Properties

Ti offers beneficial mechanical and chemical properties with respect to the automotive industry. These are the chemical properties of Ti metal:

Weight Reduction and Performance

Due to low atomic mass and density, i.e., 47.87 u and 4.5 g/cm³, it is an essential metal used in the automotive industry for weight reduction. Due to a reduction in weight, the performance automatically gets better because fuel efficiency and speed increase.

Heat Resistance and Durability

Ti is a durable metal at high temperatures because it has a high melting point of 1668 °C. Due to the Titanium Oxide (TiO₂) layer, it resists high-temperature oxidation very well while keeping its high strength.

Corrosion Resistance

Ti readily reacts with oxygen and forms a protective layer of Titanium Oxide (TiO₂). This passive layer repairs itself quickly if scratched or damaged. This layer is resistant to moisture, rust, seawater, and most chemicals.

Common Titanium Car Parts

Let's figure out some common titanium car parts in this section.

1. Powertrain and Exhaust

This part is responsible for transferring the power from the pistons to the crankshaft. Powertrain requires high strength with low weight and must be fatigue and heat-resistant. Ti is used in this part because it fulfills all these requirements.

Exhaust directs and expels exhaust gases, so it should be heat and corrosion-resistant, which is why Ti is used here in this part.

2. Driveline and Transmission

In this part of a car, Ti is used because of its high strength-to-weight ratio and fatigue strength. For transferring power from the engine to the car's wheels, a driveline is used.

Transmission components, such as gears, transmit torque, change speed, and torque ratio. Ti provides high strength, wear, and corrosion resistance.

3. Chassis and Suspension

Chassis provide structural support for vehicles, so they should be stiff, strong, and corrosion-resistant.

In a car, the suspension arms connect the wheels to the chassis, and they absorb shocks. Here, Ti is used due to its lightweight, stiffness, strength, and fatigue resistance.

4. Braking System and Heat Control

The braking system generates heat due to friction while stopping a very fast-moving car. To make the braking system wear-resistant while keeping the strength and resistance to heat, Ti is required.

5. Body, Aero and Exterior Hardware

Ti is used in the following parts because:

• Fasteners/Bolts/Screws hold the body firmly, so durability is required
• Aero components, such as spoilers, wing mounts, improve downforce and stability, so stiffness and high strength-to-weight ratio are required.
• Exterior trims, like branding or decorations, should be visually appealing.

Common Titanium Grades Used in Auto Parts

Out of many Ti grades, the automotive industry uses grades 2, 5, 9, and 23 of Ti. This section discusses the properties of these grades and in which parts each grade is used.

Ti-6Al-4V (Grade 5)

Grade 5, i.e., Ti (Ti-6Al-4V), is the strongest grade of all the Ti grades because of the precipitation strengthening phenomenon. It shows:

• High strength
• Lightweight (60% of steel)
• Performs best up to 400 °C
• Good fatigue and corrosion resistance

Due to these properties, it is used in powertrain (connecting rods, valves, etc.), suspension (control arms).

Grade 23 (Ti-6Al-4V ELI).

It is extra-low-interstitial (ELI), the same as grade 5 of Ti, but has lower contents of Nitrogen and Oxygen, due to which it is tougher, ductile, and crack-resistant. These properties make it able to be used in high-stress, critical parts of a car. This grade is used in:

• Turbo compressor wheels
• High-strength fasteners
• Fuel injector components
• Mounting brackets in motorsport

Grade 2 (Commercially Pure)

It is a commercially pure grade of Ti; due to the machine strength and hardness in this grade of Ti being compromised, but it offers excellent formability and very high corrosion resistance than others. This grade is the best choice for the following parts of a car:

• Heat Sheilds
• Intercooler & Radiator Tubing
• Fluid lines

Grade 9 (Ti-3Al-2.5V)

This grade of Ti has 3% Al and 2.5% V, which provides it with medium strength between grades 2 and 5. It has higher strength than grade 2 and more formable than grade 5. It is used in:

• Tubular Exhaust System
• Roll-cage Tubes
• Hydraulic Lines

Manufacturing Processes for Titanium Parts

Ti is very hard to machine due to low thermal conductivity, retains high strength at high temperatures, elasticity, and chemical reactivity. To machine this kind of material, advanced CNC operations are used to make Ti car parts. These are some machining operations used in the manufacturing of Ti car parts.

CNC Machining Titanium Parts

Ti is used in making multiple car components, such as engine and powertrain components, exhaust system, drivetrain, etc. From raw Ti to final shape, these CNC operations are used:

CNC Milling Process

A CNC milling operation is required to convert a raw material into the designed shape. In this process, moving cutting tools remove material from the stationary workpiece. The parts manufactured using a CNC milling operation include valve covers, cylinder head components, timing chain guides, exhaust flanges, shift forks, gearbox and plates, etc.

CNC Turning Process

A CNC turning operation is used when the design is cylindrical and requires dimensions with tight tolerances. The parts, such as crankshaft main journals, fuel injector bodies, cam followers, shift rods, tie-rod ends, etc., are manufactured using this process.

Precision Parts Machined

For precision-machined parts, 5-axis CNC machines are used, because of:

• Complex geometries
• Reduced setups
• Tool life extension
• Tighter tolerances
• Better surface finish

Why Choose CNC Machining?

The reason is that Ti is used in high-performance vehicles, due to which tight-tolerance parts are machined. Only CNC machines can achieve that tolerance, so that's why CNC machining is the first choice in the automotive industry.

Challenges of Machining Titanium

• Low thermal conductivity, so heat accumulates in the workpiece during the machining process
• The very high hardness of Ti results in tool wear
• High chemical reactivity with tool materials results in galling, adhesion, etc
• Low modulus of elasticity causes vibration and chatter during machining

Design Rules for Titanium Parts on Vehicles

This section guides how Ti metal parts should be designed to achieve maximum efficiency.

Factors to Consider on Vehicles

1. Cost, because Ti is an expensive metal due to its very difficult machining
2. Use where the strength-to-weight ratio is the primary requirement
3. Use where fatigue strength is required
4. For welding, make sure the environment is inert because Ti metal is very reactive
5. Excellent choice for corrosive environments

Stiffness vs Strength

The following graph shows that stiffness and strength are in direct relation to each other. As the strength increases, stiffness also increases.

Threaded and Tapping

Threading: For external threads, such as for bolts or studs

Tapping: For internal threads, such as in holes

Use slow speed, strong tooling, coolant, and a rigid setup for clean Ti threads.

Custom Solutions

For the best custom machining, come to TUOFA CNC Machining. We are equipped with expert professionals and advanced machines. We will assist you from design to machining and surface finish. You will get all of these services at one location at competitive prices and fast delivery times.

Surface Treatments on Titanium Car Parts

After machining, the surfaces of machined parts often have some scratches on them. To remove those scratches, surface treatments are applied to the Ti car parts to make them durable.

Anodized Titanium Car Parts

Through this method, an oxygen layer is applied through electricity, which acts as a barrier between the environment and the substrate's surface.

Burnt titanium color is produced on the surface using heat. It is also an oxygen layer and works as a protective layer against corrosion, just applied differently, compared to anodizing.

Nitriding, PVD and DLC

• Nitriding

Nitriding is a surface treatment through which the surface of titanium car parts is made harder and wear-resistant. In this method, nitrogen is introduced into the surface at an elevated temperature.

• Physical Vapor Deposition

First, the coating material is sublimated into vapors, which further deposit on the surface. For decoration and protection of Ti car parts, a very thin layer of Cr is applied through this process. This process is performed in a vacuum.

• Diamond-like Carbon (DLC)

This group of carbon-based coatings offers exceptional wear resistance and durability to Ti car parts, such as car engine parts (valves, pistons, etc.), due to the high hardness of diamond and the low friction of graphite.

Titanium vs Aluminum vs Stainless by Part

This section compares Ti metal with different steel grades in the different parts of a car.

Exhaust Systems: Ti vs 304/321 Stainless

Here is why you should choose Ti over stainless steel in the exhaust systems of a high-performance car:

Fasteners: Ti vs Class 10.9/12.9 Steel

Ti is an ideal material if you need high strength and corrosion resistance while keeping the weight low.

Suspension Hardware: Ti vs 7075 Aluminum

For normal cars, 7075 Al is used in the suspension hardware.

Brake Hardware: Ti Shims vs Stainless Shims

For excellent performance, Ti shims are preferable compared to stainless steel shims.

Titanium VS Carbon Fiber Race Car Parts

Carbon fiber is also very strong and even lighter than Ti metal, still Ti excels in many important properties.

Titanium Parts in Motorcycle Cars

1. Lighter weight→ faster acceleration & better handling
2. Higher strength → stronger parts at lower weight
3. High heat resistance→ better exhaust & turbo performance
4. Excellent fatigue resistance→ longer life at high RPM
5. Corrosion resistance→ zero rust, longer durability
6. Stiff + tough→ precise control in suspension & chassis parts

Conclusion

Ti has made its strong position in the automotive industry because of its excellent mechanical properties. It is used in high-performance racing cars, where fast speed with high strength, light weight, and high durability is required. Ti is an expensive metal because of its mechanical properties and difficult machining, and formability. If you are going to planning a new project for a high performance vehicles, then Ti is the best choice, though expensive.

FAQs

Does titanium react with salt water?

No, because of the TiO₂ layer on the surface. It is a very thin and strongly adherent layer acts as a barrier between water and surface.

Why isn't titanium used in all cars?

Because it is a very expensive metal due to its excellent mechanical properties and difficult machining.

Which car parts benefit most from titanium?

High-performance racing cars, such as Formula 1 and MotoGP bikes, benefit most from titanium.