Author: Site Editor Publish Time: 2025-12-25 Origin: Site
In the carbon fiber material industry chain, the processing method of semi-finished products directly determines the performance, structural integrity, and application scope of the final product. Understanding the mainstream processing techniques for semi-finished carbon fiber products is crucial for product manufacturers, technical engineers, and even end customers. This article will provide a detailed analysis of four common semi-finished carbon fiber processing methods: prepreg molding, pultrusion, filament winding, and compression molding, to help you better understand their principles, advantages and disadvantages, and application scenarios.
Prepreg is a semi-finished product made by pre-mixing a carbon fiber matrix (such as unidirectional fabric or textile) with a resin system (such as epoxy or phenolic). It offers excellent controllability, storage properties, and a consistent fiber volume ratio.
Cutting and Laying: Prepreg sheets are cut according to mold dimensions.
Mold Positioning and Vacuum Bag Packing: Prepreg layers are placed into the mold and vacuum bagged. Heat Curing: Typically cured in an autoclave or hot press.
Aerospace structural parts
High-end sports equipment (e.g., carbon fiber bicycle frames)
Medical device housings
| Advantages | Disadvantages |
| Good material uniformity | High equipment investment cost |
| Controllable resin content | Requires high storage and transportation conditions |
| High molding quality | Relatively long process cycle |
Pultrusion is a process for continuously producing carbon fiber composite profiles. Resin-impregnated carbon fibers are continuously drawn into a heated mold, where they are cured at high temperature to form a semi-finished structure with a fixed cross-section.
Carbon fiber yarn bundle → Resin tank impregnation → Molding mold heating and curing → Drawing → Cutting
Carbon plates for building structural reinforcement
Electric composite insulating rods
Carbon fiber window frames and curtain wall profiles
High efficiency: Suitable for large-scale production of standard parts
High dimensional accuracy: Automated molding with excellent error control
Stable mechanical properties: Uniform fiber orientation and high tensile strength
Filament winding involves winding a continuous carbon fiber tow at a specific angle around a rotating mandrel under controlled tension, followed by curing to set the shape. The winding angle, tension, and fiber alignment determine the structural strength and stiffness.
Wet Winding: Fibers are impregnated with resin before winding
Dry Winding + Prepreg: Winding is performed using prepreg
Pressure vessels, hydrogen storage tanks
Piping systems (e.g., in the petroleum and chemical industries)
Aircraft propeller shaft sleeves
High control system requirements (angular errors affect stress distribution)
Low initial winding efficiency
Prone to air bubbles and uneven resin content, requiring degassing
Compression molding, also known as hot press molding, involves placing cut carbon fiber prepreg or SMC/BMC composite material into a metal mold and pressing it into the desired shape using heat and high pressure.
Complex structural parts: such as automotive interior brackets and drone casings
High molding efficiency: Suitable for medium-volume rapid prototyping
Good consistency and repeatability
Mold heating uniformity must be controlled
Pressure should be stable and sufficient
Mold release agents should be compatible with the carbon fiber resin system to avoid affecting surface quality
Comparison of Carbon Fiber Processing Methods
| Processing Method | Advantages | Disadvantages | Applications |
| Prepreg molding | High-quality molding, suitable for complex structures | High equipment cost and long cycle time | Aviation, medical, and sports equipment |
| Pultrusion | High efficiency, low cost, continuous production | Shapes are limited to fixed cross-sections | Buildings, bridges, and electrical components |
| Film winding | High structural strength, suitable for pressure vessels | Complex process control and long cycle time | Pressure vessels, gas pipelines, etc. |
| Compression molding | Moderate cost and good batch consistency | High mold development cost and limited applicable structures | Automobiles, drones, industrial casings, etc. |
Different product structures, performance requirements, cost budgets, and batch sizes all influence process selection:
For customized high-performance parts: Prepreg molding is preferred.
For mass production of standard profiles: Pultrusion is the most cost-effective.
For containers or tubular parts: Winding is preferred.
For rapid tooling and consistent production: Compression molding offers advantages.
Processing technology for carbon fiber semi-finished products is a critical step in the composites industry. A thorough understanding of the technical characteristics of various molding methods will help manufacturers improve product performance and market competitiveness. Revolve CF will continue to provide customers with professional materials and solutions.
To purchase or wholesale carbon fiber materials, please contact Revolve CF at HarveyXu@revolve-cf.com or visit our website: https://www.revolve-cf.com.
