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About CFRP

What is CFRP?

Carbon Fiber Reinforced Plastic (CFRP) is a composite material that combines tough carbon fibers and a matrix resin to anchor them.
Carbon fibers are lightweight yet have an extremely high tensile strength and rigidity. In CFRP, a resin firmly bonds the carbon fibers together to provide shape retention, impact resistance, and environmental resistance. This combination gives CFRP a specific strength and specific stiffness that far exceed those of conventional metal materials, while also providing superior heat and corrosion resistance.
For this reason, CFRP has been adopted in a wide range of fields, including aircraft, automobiles, industrial robots, and sporting goods. It is attracting attention as the ideal material for products that require lighter weight and higher performance.

Properties and Advantages of CFRP

Lightweight and High Strength
CFRP is significantly lighter than other metals such as steel while maintaining the same strength. It also offers a high degree of design freedom, enabling the optimal design of components for each application.
Low Thermal Expansion and High Vibration Damping
CFRP’s thermal expansion coefficient is approximately one-tenth that of metals, resulting in low distortion due to temperature changes and excellent vibration damping performance.
Corrosion Resistance and X-ray Permeability
CFRP is less likely to corrode than metals. Another major advantage of CFRP is the ease with which X-ray inspection and non-destructive testing can be performed.

Difficulties in Cutting CFRP

Because CFRP is a composite material, it has inherent difficulties in machining.

Carbon Fiber Directionality and Cutting Resistance

  • Influence of Anisotropy

    The strength of carbon fiber in CFRP is concentrated in one direction, so its angle relative to the tool during cutting greatly affects machining accuracy and surface quality.

  • Effects of Laminated Structure

    Because the resin matrix of CFRP is combined with carbon fibers of varying hardness, drilling may cause the fibers to crack or may result in delamination between layers.

Tool Wear and Cutting Conditions

  • Need for Special Tools

    Carbide or diamond-coated tools are required instead of general high-speed steel (HSS).

  • Optimal Machining Parameters

    It is essential to select the appropriate rotational speed, cutting temperature, and cutting edge movement. Dry machining is generally recommended for CFRP, and the use of cutting fluid should be avoided.

Cautions for Drilling Process

In addition to the difficulties of turning and cutting in general, the following points must be considered when drilling CFRP.

Cutting of Carbon Fiber
When the cross section of carbon fiber is perpendicular to the tool, the fiber is prone to cracking and delamination. This may cause end-face roughness and reduced strength of parts.
Delamination Phenomenon Specific to Laminated Materials
In laminated materials, delamination between the layers is noticeable, so optimization of processing conditions and preliminary testing are essential.
Finish after Machining
With the right processing parameters and tool selection, high-quality drilling that is comparable to metal processing can be achieved. However, it is important to determine which holes are required in advance and design changes may be necessary.

Processing Methods and Their Effects

Since the properties of CFRP vary depending on the processing method, an understanding of the processing method is required before cutting.
The main processing methods for CFRP are as follows:

Autoclave Molding
Produces high-quality CFRP products, also known as dry carbon. Also effective as a process for prototyping and small-lot production.
RTM, Va-RTM, Press Forming, Filament Winding, and Other Methods
Various processing methods exist depending on the application and shape. Each method requires specific expertise.

Safety Measures and Environmental Management during Processing

CFRP processing generates fine chips, which can be harmful to the human body and machinery.

Effects on the Human Body
CFRP dust can damage the respiratory tract if inhaled, and its contact with skin can cause itching and injury. Appropriate dust control measures and the use of protective equipment are essential.
Effects on Machinery
Regular cleaning and inspection of machinery are important because fine chips can enter bearings and sliding parts, causing wear.

CFRP Machining Services by NAKANO

We offer the following strengths in CFRP cutting:

One-Stop System
We provide high-quality products through an integrated process that encompasses design, analysis, molding, machining, coating, inspection, and testing.
High Precision Equipment
We make full use of large, five-axis, high-precision machining centers to ensure consistent results, even when working with complex shapes or under special conditions.
Expertise and Extensive Experience
Our engineers are well-versed in the properties of CFRP. We promote efficient and highly accurate machining by providing optimal machining conditions, tool selection, and process control.

We propose the best materials and processing methods for your application and environment. Please contact us to discuss weight reduction, cost reduction, and the production of high-quality CFRP parts. We promise to respond flexibly.

CFRP is an advanced lightweight material with high strength and heat resistance. Due to its unique properties, advanced technology and specialized tools are required for its machining and drilling. By comprehensively considering molding methods, processing conditions, and environmental management, CFRP can achieve a level of precision and quality equal to or better than metals.
We are capable of handling all issues related to CFRP processing based on our extensive knowledge and advanced facilities. Please feel free to contact us for a consultation.

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