CFRP applications in automobiles are increasing. As an excellent lightweight material, CFRP also has high-temperature resistance, corrosion resistance, and vibration-damping properties. Its products have a cool appearance. Therefore, it is increasingly favored by automotive engineers.
Detailed CFRP Applications in Automobiles
Wheel Hubs
Wheel hubs account for a significant proportion of automotive components. They bear the entire vehicle weight, so the requirements for wheel hubs in the manufacturing process are extremely high. They need to have strong impact resistance, as well as good safety and wear resistance.
Wheel hubs of carbon fiber composites can meet these requirements while reducing vehicle weight. During vehicle operation, the greater the vehicle’s weight, the greater its inertia, meaning weight and inertia are directly proportional. Wheel hubs made of carbon fiber composites can minimize inertia while maintaining good performance.
Body Components
Comparing CFRP with traditional metal materials, the specific strength and stiffness of composite materials are significantly higher than ordinary metal materials. Under the same structural strength conditions, using CFRP to make auto parts can reduce weight by 50%, which has an important role in improving the vehicle’s dynamic.
Brake Discs
CFRP has many excellent characteristics, making it an ideal material for manufacturing brake discs. These characteristics include:
| Its friction coefficient remains between 0.35-0.40, with good stability and suitability, ensuring the vehicle remains stable during braking.
| CFRP’s heat resistance can reach up to 2500°C, and it has strong resistance to humid heat and aging.
| CFRP’s oil resistance, water resistance, and corrosion resistance make it an ideal material for manufacturing brake pads.
Drive Shafts
To ensure stable vehicle operation, drive shafts should have good transmission ability and fatigue resistance. CFRP’s unique anisotropy and high specific strength make it possible to reduce the weight of drive shafts by more than half when applied. Under the same conditions, compared to traditional metal materials, its torque can reach over 170% of steel. Moreover, the use of CFRP can significantly improve the durability and fatigue resistance of automotive drive shafts.
Interior/Exterior Trims
| Exterior Trims: CFRP is more widely used in exterior trims, especially for high-end luxury vehicles. Due to the high cost of CFRP, exterior trims are often offered as high-end optional equipment or as aftermarket sports kits. CFRP sports kits cover a wide range, mainly including body panels and exterior trim, such as hoods, intake grilles, headlight trim, front lips, side skirts, mirrors, door trim strips, rear spoilers, and wings.
| Interior Trims: For interior trims, given the attractive appearance of carbon fiber that can bring a dazzling style to the whole vehicle, most models use carbon fiber film for interior modification and promotion. This is mainly because automotive interior parts are primarily made of polypropylene (PP) plastics, and CFRP doesn’t offer significant advantages in weight reduction, but would instead lead to a surge in costs. Therefore, the lower-cost film application method is usually adopted.
Car Doors
CFRP car doors have shown significant improvements in modal, stiffness, strength, crash intrusion amount, and speed compared to metal doors while reducing weight by 54.94%.
Trends in CFRP Applications in Automobiles
| Lightweight design is one of the main driving forces behind the application of CFRP in automobiles. Vehicle weight reduction can improve fuel efficiency and significantly reduce carbon dioxide emissions. However, the high cost of CFRP and the difficulty of development technology are not manageable for ordinary companies.
| An attractive appearance is also a driving factor in the CFRP application. The use of CFRP in automotive exterior parts directly gives a sense of technology, dynamism, sportiness, and fashion, which is more likely to attract young consumers.
Problems Faced by CFRP Applications in Automobiles
CFRP has characteristics such as low density, high modulus, and high specific strength, making it an ideal material for automotive lightweight design. However, the application of CFRP in the automotive field still faces some problems.
| High cost: Commonly used carbon fiber prepregs are basically above 15 USD/kg. Comparing the prices of commonly used carbon fiber prepregs (CFRP raw materials) and automotive steel, the cost of carbon fiber prepregs is more than 15 times that of steel. Although the use of CFRP can achieve weight reduction of about 40%, the overall raw material cost far exceeds existing steel materials.
| Complex processes: Traditional metal stamped parts generally go through sheet metal cutting – stamping forming – and packaging. The process of manufacture is relatively simple. However, CFRP parts are relatively more complex. At the same time, the design of CFRP automotive parts is more challenging and requires experienced designers.
Research on CFRP Applications in Automobiles
CFRP is formed by carbon fiber through resin molding. Based on the resin used as the matrix, it can be divided into two types: thermoset CFRP (CFRTS) and thermoplastic CFRP (CFRTP).
Currently, CFRTS is mainstream, with its strength and reliability meeting aircraft adoption standards. However, both material and manufacturing costs are high, limiting its application only to aerospace and high-end automotive fields.
To address this issue, further research and development on CFRTP is needed. Thermoplastic resins have the property of softening when heated and hardening when cooled, without chemical reactions. This property is maintained regardless of how many times heating and cooling are repeated. Therefore, it is suitable for injection molding and short-time press molding, making it a very cost-effective material for mass production.
When using thermoset resin in CFRTS, waste materials are produced during the manufacturing process, which is difficult to recycle. However, with thermoplastic CFRP, it’s possible to recycle waste materials from the manufacturing process.
In conclusion, CFRP has broad application prospects in automobiles. However, due to factors such as high costs, CFRP is currently mainly applied to some high-end vehicles.
CFRP Provider: Tengye
At Tengye, we’re thrilled to be early participants in your new projects. Our passion for magnets extends from material selection and design optimization to providing magnetic solutions. We hope to bring our knowledge and experience to the forefront by actively engaging in your upcoming projects.
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