Carbon Fibre in Medical Technology
Properties, Applications and Use Cases
Industry Insight: Carbon Fibre increasingly used in Medical technology, equipment and infrastructure applications.
Carbon Fibre-Reinforced Polymer (CFRP) materials are increasingly being adopted in medical technology due to their exceptional mechanical performance. In this piece, we’ll explore which of Carbon Fibre’s properties make it suited to such applications, and discuss some of the engineering advances.
What are the beneficial mechanical properties of Carbon Fibre?
The main properties that are cited as reasons for replacing traditional materials with Carbon Fibre are well documented. These include:
- High strength-to-weight ratio
- Design flexibility
- Ability to be engineered to be anisotropic (able to be custom manufactured (using specific manufacturing methods) to withstand exact forces that will be applied on the part)
- Thermal Stability – Near Zero Thermal Expansion
- Chemical resistance
- Radiolucency
- Environmental resistance
- Vibration damping
With advancements in the medical technology sector, engineers and designers are increasingly adopting composites/carbon fibre within their projects to develop devices and infrastructure that meet demanding clinical, ergonomic, and safety requirements. Whilst applications vary, we explore in more detail those properties that are providing the greatest benefits and facilitating advancement in the sector.
Carbon Fibre properties most relevant to medical applications
High Strength-to-Weight Ratio
Carbon Fibre exhibits high tensile strengths and stiffness values in the range of 200–600 GPa depending on fibre grade and laminate design. This results in components that outperform traditional metals at a fraction of the mass.
Lightweight Carbon Fibre structures (or equipment) provide systems savings for the clinician by improving device handling, reducing operator fatigue, and enabling dynamic or robotic systems.
Radiolucency
Radiolucency is the term used in medical imaging to describe areas or substances that allow radiation to pass through them with minimal absorption. In this regard, Carbon Fibre is ideally suited for applications in medical imaging equipment owing to its near transparency to X-rays, CT, and fluoroscopy.
Equipment or structures that are made of Carbon Fibre produce minimal artefacts in the resultant imaging. This allows the clinician to achieve higher-quality diagnostic images, unaffected by the material properties of the equipment upon/around which the patient is positioned.
This property means that Carbon Fibre provides a high degree of imaging compatibility and is therefore providing highly beneficial in equipment such as imaging tables and patient positioning devices.
Chemical Resistance
Carbon Fibre has a high level of resistance to corrosion. In other sectors, this is relevant to environmental conditions, but in the case of medical applications, this ensures the piece of equipment is unaffected by bodily fluids, medical liquids, disinfectants and sterilisation techniques which are essential for maintaining patient safety. Moreover, proper matrix selection (e.g., epoxy or PEKK) ensures that surfaces are created that are non-reactive, biocompatible, and unlikely to harbour bacterial growth when properly sealed.
Design Flexibility
Designing the laminate is the cornerstone of manufacturing Carbon Fibre parts that are suited to their final application. Carbon Fibre parts are manufactured by placing layers of pre-impregnated carbon fibre (known as pre-preg) around a mandrel or in a mould in precise orientations (e.g., 0°, ±45°, 90°). This means the laminates are tailored exactly for stiffness, flexibility, and dynamic response through fibre orientation, and the part can therefore be crafted to meet the needs of the final application.
This anisotropy is valuable for prosthetic production, surgical instruments, and precision robotic components where directional mechanical performance must be optimised. Notwithstanding the cost implication, this manufacturing technique and material property provides for individualised design and manufacture which has been used in the case of specific prosthetics and assistive technologies.
Thermal Stability
Carbon Fibre’s environmental resilience and thermal stability is also well documented and hence is suited to applications where consistency under varying conditions is essential. With near zero thermal expansion, Carbon Fibre offers geometrical stability even when subject to temperature fluctuations. This is applicable in the case of imaging equipment/structures, where higher levels of precision are required.
Equally, Carbon Fibre offers good vibration damping compared to metals, which increases accuracy in robotic surgery systems.
