Pultruded CFRP square tube made from IM carbon fibres with an epoxy resin matrix. The profile is lightweight, very stiff and particularly suitable for structures where high flexural and tensile stiffness in the longitudinal direction are required.
Thanks to its unidirectional fibre orientation, the carbon square tube offers high
performance along the profile axis. It is suitable for technical frames, model making,
UAV structures, robotics, jig and fixture construction, and high-stiffness lightweight
structures.
- Pultruded CFRP square tube / carbon square tube
- IM carbon fibres Torayca® T800
- Epoxy resin matrix with unidirectional fibre orientation
- High fibre volume fraction of approx. 62 %
- Very high stiffness and tensile strength in the longitudinal direction
- Low weight and good dimensional accuracy
Detailed Description
The pultruded CFRP square tubes from DPP™ are made from IM carbon fibres Torayca® T800 and an epoxy resin matrix. In the pultrusion process, the carbon fibres are continuously pulled through a heated die and fully impregnated with resin. This produces precise CFRP profiles with a predominantly unidirectional fibre orientation.
The fibres run mainly in the longitudinal direction of the profile. This results in particularly high tensile and flexural stiffness along the profile axis. This is ideal for lightweight, slender load-bearing structures where weight needs to be reduced without compromising stiffness.
Compared with CFRP profiles made from standard HT carbon fibres, the IM fibres used here offer higher stiffness and tensile strength with almost comparable elongation at break. The carbon square tube is therefore particularly suitable for applications requiring higher mechanical reserves and good dimensional accuracy.
The high fibre volume fraction of approx. 62 % and the low void content ensure consistent quality of the pultruded profile. The epoxy resin matrix provides good temperature resistance and makes the profile suitable for demanding technical applications in composite and lightweight construction.
Typical Applications
- Lightweight structures with high stiffness
- Technical frame structures and beams
- Model making, model aircraft construction and UAV structures
- Robotics and automation technology
- Measuring equipment, jigs and fixtures
- Mechanical engineering and technical prototypes
- High-stiffness support and connecting elements
Advantages of IM Carbon Fibres
IM carbon fibres offer higher mechanical performance than conventional standard HT carbon fibres. With the same profile dimensions, stiffer and more load-resistant profiles can be achieved. This is particularly advantageous where installation space is limited or where the component must remain as lightweight as possible.
| Stiffness | approx. 20 % higher than standard HT carbon fibres |
| Tensile strength | approx. 25 % higher than standard HT carbon fibres |
| Elongation at break | almost identical to standard HT carbon fibres |
Bonding and Assembly
CFRP square tubes can be bonded well in structural designs. Epoxy adhesives are suitable for durable joints; depending on the application, cyanoacrylate adhesives can also be used for quick fixation.
For load-bearing bonds, the bonding surfaces should be clean, dry and free from dust, grease and release agents. In practice, it is advisable to lightly sand the bonding area and then clean it carefully. This provides a reliable bonding surface for structural or semi-structural joints.
Practical Machining Notes
Fine-toothed saw blades, diamond tools or suitable carbide tools are recommended for cutting and machining CFRP profiles. Holes should be drilled using sharp tools, keeping edge fraying as low as possible.
Conductive carbon dust is generated when sawing, sanding or drilling CFRP. Dust formation should be minimised, extraction should be used and suitable personal protective equipment should be worn. Electrical components and exposed contacts should be protected from carbon dust.
Technical Data
| Profile shape | Square tube / rectangular hollow profile |
| Outer dimensions | 10.0 × 10.0 mm |
| Inner dimensions | 8.0 × 8.0 mm |
| Length | 500 mm |
| Material | IM carbon fibre / epoxy resin matrix |
| Fibre de carbone | Torayca® T800 |
| Fibre orientation | Predominantly unidirectional in the longitudinal direction |
| Fibre volume fraction | approx. 62 % |
| Heat deflection temperature | jusqu'à 120 °C |
| Manufacturer | DPP™ – Van Dijk Pultrusion Products |
Tolerances
| Outer dimensions | − 0.1 mm |
| Inner dimensions | ± 0.1 mm |
| Length | + 5 mm |
| Straightness | 2 mm / 1000 mm |
Compatible Products
Epoxy adhesives are suitable for durable bonded joints. For quick fixation or small assembly tasks, cyanoacrylate adhesives can be used depending on the application. Suitable tools for CFRP machining and effective dust extraction are recommended for cutting and finishing work.
FAQ
What is a pultruded CFRP square tube used for?
It is suitable for lightweight and stiff frames, beams, reinforcements, fixtures, model making and UAV structures, as well as technical constructions subjected to high loads in the longitudinal direction.
What is the advantage of IM carbon fibres?
IM carbon fibres provide higher stiffness and tensile strength compared with standard HT carbon fibres. This allows particularly high-performance lightweight profiles to be manufactured.
In which direction is the profile particularly load-bearing?
Due to the predominantly unidirectional fibre orientation, the profile is particularly stiff and tensile-resistant in the longitudinal direction. Transverse loads, local pressure points and drilled holes should be taken into account in the design.
Can the CFRP square tube be bonded?
Yes. Epoxy adhesives are particularly suitable for durable joints. Depending on the application, cyanoacrylate adhesives can also be used for quick fixation.
What should be observed when machining CFRP profiles?
Carbon dust is generated when sawing, drilling or sanding. Dust formation, inhalation and carry-over should therefore be avoided. Dust extraction and suitable personal protective equipment are recommended.
