Carbon fiber square tubes are renowned for their high strength and lightweight properties. Used in aerospace, automotive, and various industrial applications, these tubes are crucial in reducing weight while maintaining structural integrity. This article details the manufacturing processes involved in producing high-quality carbon fiber square tubes.
This method uses external force to pull the carbon fiber or its fabric into glue, extrude, heat and cure, and cut to length to continuously produce carbon fiber square tubes. The advantages of pultrusion are that it can realize automated production, high production efficiency, high fiber content, and high product strength, but the shape is single and the transverse strength is low.
Automated control and high production efficiency
Fiber content up to 80%, high product strength
No scraps, labor saving, raw materials saving, and energy saving
Product quality is stable, repeatability is good, length can be cut arbitrarily, and cost is low
Single shape, only linear profiles can be produced
Single fiber direction, low transverse strength, high longitudinal tensile strength
Not environmentally friendly
Compression molding uses prepreg, which is cut and stacked and placed in a mold, and then heated and pressurized to cure. Compression molding can flexibly design the laying method, and the products produced have precise dimensions and good mechanical properties, which are suitable for the production of high-performance carbon fiber composite pipes.
The prepreg laying angle is flexible, and the laying method can be designed according to the stress conditions
Accurate and stable dimensions, good mechanical properties, and controllable resin content
Suitable for the production of high-performance carbon fiber composite pipes
Low degree of automation, slow production efficiency
High product cost
Product size is affected by the size of the mold and equipment
This method rolls the carbon fiber prepreg layer on the mold and cures it by heating. The advantage of roll molding is that it can produce carbon fiber square tubes with excellent performance, especially the tubes with long fiber continuous layer have better performance and are suitable for applications with higher requirements
It can produce carbon fiber square tubes with excellent performance
Long fiber continuous layer, better performance, excellent impact resistance and load-bearing performance
It needs manual rolling and low automation
There may be bubbles, which require professional technology and tools to avoid
Autoclave molding is a molding process that uses high temperature and high pressure, which is suitable for manufacturing carbon fiber square tubes with complex structures or high performance requirements. By curing the prepreg under high temperature and high pressure, the high quality and high performance of the product are guaranteed.
High temperature and high pressure curing, ensuring high quality and high performance of the product
Applicable to manufacturing square tubes with complex structures or high performance requirements
High cost
Requires professional equipment and long production time
This method is an improvement on compression molding. It uses a bladder instead of a metal core mold. The carbon fiber composite material is pressurized by the expansion force of the bladder, and the metal outer mold is pressurized and heated to cure the carbon fiber composite material. Suitable for manufacturing carbon fiber square tubes with complex structures that do not require high inner wall requirements.
Suitable for manufacturing carbon fiber special-shaped pipes with complex structures
The process principle is similar to compression molding, and the smoothness of the inner wall is determined by the material of the airbag
Most of the airbag materials are disposable consumables, which increases the manufacturing cost
The inner dimension tolerance is large and assembly is difficult
This process uses a winding machine to wind the carbon fiber filaments on the core mold, winds according to the required pattern and thickness, and then cures in an oven. The advantage of winding is that the arrangement direction of the fibers can be precisely controlled, and the produced carbon fiber square tubes have high strength and high performance
The fiber arrangement direction is precisely controlled, and the produced pipes have high strength and high performance
Suitable for mass production
Complex equipment and process
High cost
At Dronecarbon, we use the compression molding method for producing our carbon fiber square tubes. This method ensures high precision, superior strength, and customizable properties tailored to our clients' specific needs. Here is a detailed look at the compression molding process:
Custom Mold Creation: Design the mold based on the specific dimensions and specifications provided by the client. This includes creating the inner core mold, as well as the male and female molds. High-strength steel molds are often used to ensure durability and precision.
Fiber Layup Design: Plan the layup sequence for the carbon fiber prepreg, considering the required strength and performance characteristics. The prepreg layers are typically oriented at 0 and 90 degrees to maximize structural integrity.
Cut the carbon fiber prepreg according to the mold dimensions. The cut prepreg layers should account for the tube’s wall thickness and overall dimensions. This step is crucial for ensuring the final product meets the specified requirements.
Layering: Lay the cut prepreg layers onto the mold, ensuring each layer is properly aligned and free of air bubbles. This step requires precision and attention to detail to achieve optimal performance.
Compression and Heating: Place the prepared mold into a compression molding press. Apply heat and pressure according to the prepreg specifications. This typically involves heating the mold to around 120°C and applying significant pressure to ensure proper curing and consolidation.
Maintain the temperature and pressure for the required curing time, usually around 2 hours. Once the curing process is complete, allow the mold to cool gradually.
Demolding: Carefully remove the cured carbon fiber tube from the mold. The use of a high-temperature release agent during mold preparation aids in this process, ensuring the tube does not adhere to the mold.
9.
Post-Processing
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Trimming and Machining: Trim any excess material and perform necessary machining operations to achieve the final dimensions and surface finish. This may involve using lathes, milling machines, or grinding equipment.
Quality Control: Inspect the finished product for any defects or irregularities. This includes checking dimensions, surface quality, and structural integrity to ensure the tube meets all specifications.
Material Selection: The choice of carbon fiber prepreg and resin system is critical. High carbon content resins ensure superior strength and durability.
Temperature and Pressure Control: Maintaining precise temperature and pressure during the curing process is essential for achieving optimal material properties.
Mold Design: Accurate and robust mold design is crucial for producing high-quality tubes. The mold must withstand the pressures and temperatures involved in the process.
Layup Precision: Proper alignment and orientation of the carbon fiber layers are necessary to achieve the desired mechanical properties.
Quality Assurance: Rigorous quality control measures must be implemented at every stage to ensure the final product meets the required standards.
This completes the entire production process of carbon fiber square tubes. The resulting tubes are characterized by high strength, lightweight, and stable structure. They offer excellent impact and bending resistance, as well as superior anti-aging and corrosion-resistant properties, making them highly popular. However, compared to traditional plastic or metal materials, carbon fiber square tubes are significantly more expensive. The pricing of carbon fiber square tubes is influenced by several factors:
The pricing of carbon fiber square tubes is primarily influenced by three factors: size specifications, production difficulty, and performance.
Size Specifications: The larger the size, the higher the price. This is because larger tubes require more carbon fiber raw materials, increasing the material cost. Additionally, larger tubes need bigger equipment, leading to higher production costs. The greater the processing volume for larger tubes also impacts the overall cost.
Production Difficulty: If the production process is more complex, the cost will be higher. For example, if high flatness is required, more labor is needed, which increases the cost. Carbon fiber square tubes are often used as fork arms, where a narrower top and wider bottom can make production more challenging, thus more expensive than standard tubes.
Performance Requirements: The desired performance of the tubes also significantly impacts the price. Higher performance tubes require more expensive raw materials. For instance, tubes made from M30 carbon fiber will be more expensive than those made from T300.
Overall, the pricing of carbon fiber square tubes is determined by these three main factors.
Producing carbon fiber square tubes involves multiple manufacturing techniques, each with its own set of advantages and disadvantages. At Dronecarbon, we prioritize quality and precision, which is why we employ the compression molding method. This technique allows us to produce high-performance, customized carbon fiber tubes that meet the specific needs of our clients.
Understanding the intricacies of each production method helps in selecting the right process for the intended application, ensuring that the final product delivers optimal performance and reliability. As the demand for lightweight, high-strength materials continues to grow, advancements in carbon fiber manufacturing techniques will play a crucial role in meeting these evolving requirements.