Detailed explanation of carbon fiber extrusion process

Pultrusion is an automated process for continuous production of carbon fiber composite profiles. It involves impregnating carbon fiber yarns with resin and pulling them through a heated mold to produce components with consistent cross-section and excellent performance. This process is widely used in the fields of construction, automotive, and infrastructure due to its high efficiency and productivity.

1、 Overview of Carbon Fiber Pultrusion Process

The pultrusion process involves impregnating continuous carbon fiber yarn or fabric with resin, pulling it into a heated mold, and curing it under constant tension and temperature to produce bars, pipes, or profiles. This method is particularly suitable for manufacturing long and straight structural components, with both high strength and lightweight characteristics.

Process characteristics

Continuous production: Achieving high efficiency and mass production..

Consistency: The cross-sectional dimensions and performance are highly consistent.

Material optimization: The fiber content can be precisely controlled..

Cost effectiveness: Suitable for standardized product production..

2、 Carbon fiber extrusion process flow

The process mainly includes the following steps:

1. Fiber preparation and impregnation

Carbon fiber yarn or fabric is released from the reel and immersed in liquid resin through a resin tank to ensure that the fibers are fully wetted.

Image 1 Description: A picture showing fiber preparation and impregnation.. The picture shows multiple rolls of carbon fiber yarn, which are impregnated through resin tanks. The liquid resin is transparent in color, and the background is a production workshop, highlighting the material preparation process.

2. Pre molding and drawing

After impregnation, the fibers enter the pre forming zone and are initially formed. They are then pulled into the heating mold at a constant speed by a pulling device (usually a clamping or track type).

Image 2 Description: A picture showing pre molding and drawing.. The picture shows that the drawing machine is working, and the carbon fiber bundle is pulled into the mold. There is a control panel next to it displaying the drawing speed, and the background is an industrial environment, reflecting the degree of automation.

3. Heating and curing

In the heated mold, the resin solidifies at high temperatures (usually 120 ° C to 180 ° C), and the fibers combine with the resin to form a stable structure. The mold temperature and drawing speed need to be accurately matched.

Image 3 Description: A picture showing heating and curing.. The picture shows that during the operation of the heating mold, there is a temperature display on the surface of the mold, and carbon fiber bundles pass through it. The background is a factory workshop, highlighting the controllability of the curing process.

4. Cutting and post-processing

The cured profile is pulled out of the mold, cut to a specified length by an automatic cutting machine, and subjected to surface polishing or coating treatment.

3、 Advantages and disadvantages of carbon fiber extrusion process

Advantages

1. High efficiency: Continuous production reduces downtime..
2. Strong consistency: The product’s cross-section and performance are highly stable.
3. High material utilization rate: reduces waste and lowers costs..
4. Design flexibility: Multiple cross-sectional shapes can be produced..

Disadvantages

1. Shape restriction: Only suitable for straight profiles with constant cross-sections..
2. High initial investment: Equipment and mold costs are relatively high..
3. Complex process: The drawing speed and temperature need to be precisely controlled..

4、 Application fields of carbon fiber pultrusion process

This process is widely used due to its unique advantages in:

Construction industry: such as reinforcing bars, bridge cables, and railings..

Automotive industry: such as drive shafts and body frames..

Energy sector: such as wind turbine blade support rods and solar brackets..

Sports equipment: such as golf clubs and arrow shafts..

5、 Future Development Trends

With the development of intelligent control technology and new resins, the carbon fiber extrusion process will achieve higher automation and production efficiency. By combining real-time monitoring and multi material composite technology, the process will be extended to more complex application scenarios to meet diverse market demands.

6、 Summary

The carbon fiber extrusion process has become the core technology for manufacturing carbon fiber profiles due to its continuous production, high consistency, and cost-effectiveness. Through fiber impregnation and pull-out curing, this process can produce high-quality linear structural components. Despite its limited shape, it has broad application prospects in fields such as construction, automotive, and energy. Future technological innovation will further enhance its competitiveness.