What are Advanced Composites?

Advanced Composites are a class of materials that are engineered by combining two or more constituent materials to create a composite material with superior properties compared to the individual components. These composites are characterised by their high-performance characteristics, which include exceptional strength, stiffness, lightweight nature, durability, and resistance to various environmental factors.

The constituents of advanced composites typically include a reinforcement material and a matrix material. The reinforcement material is usually a high-strength fibre or fabric, such as carbon fibres, glass fibres, aramid fibres (e.g., Kevlar), or natural fibres. These fibres provide the composite with excellent mechanical properties, such as high tensile strength and stiffness. The matrix material, on the other hand, acts as a binder, holding the reinforcement together and transferring the load between fibres. The matrix is often a polymer resin, such as epoxy, polyester, or phenolic resin.

The combination of the reinforcement and matrix materials in advanced composites leads to synergistic effects, resulting in exceptional material properties. The reinforcement provides high strength and stiffness, while the matric protects the reinforcement, provides toughness, and improves the overall structural integrity. The resulting composite material exhibits a combination of properties that is superior to those of the individual components.

Process Cooling and Advanced Composites 

Process cooling plays a crucial role in advanced composites research and production by maintaining controlled temperatures and providing efficient heat dissipation. Some examples of how process cooling is utilised in the context of advanced composites are below:

Temperature Control

• Advanced composites often undergo curing or polymerisation processes where the resin matrix is cured to achieve the desired material properties. Temperature control is critical during these processes to ensure proper resin cure and avoid undesirable effects such as incomplete curing, resin degradation, or dimensional distortion. Process cooling equipment, such as chillers, is used to regulate the temperature of the curing environment, ensuring that the composite material cures uniformly and consistently.

Heat Dissipation 

• During the manufacturing processes of advanced composites, such as resin infusion, resin transfer moulding, or prepreg curing, exothermic reactions occur. These reactions generate heat, which needs to be efficiently dissipated to prevent overheating and thermal damage to the composite material. Process cooling equipment is employed to remove excess heat and maintain the required temperature range, ensuring the structural integrity and quality of the final composite product.

Mould Cooling 

• In processes like composite moulding or compression moulding, moulds are used to shape the composite material. Effective cooling of these moulds is essential to accelerate the curing process, improve cycle times, and enhance overall productivity. Process cooling systems are used to circulate heat transfer fluids through the moulds, extracting heat and facilitating faster and controlled curing.

Ambient Temperature Control

• In certain advanced composites processes, such as filament winding or lay-up, ambient temperature control is critical to maintain the optimal conditions for resin application, fibre alignment, and subsequent curing. Process cooling equipment can be used to regulate the ambient temperature, ensuring consistent material behaviour and preventing variations due to temperature fluctuations.

Material Storage

• Advanced composite materials often have specific storage requirements to maintain their integrity and prevent degradation. Cooling equipment can be employed to provide controlled storage environments, such as temperature-controlled chambers, to preserve the composite materials’ properties, stability, and shelf life.

Research and Development 

• Process cooling is also vital in advanced composites research and development. Researchers often conduct experiments and testing at different temperatures to study the material behaviour, optimise processes, and characterise the properties of composite materials. Process cooling equipment allows precise temperature control during these experiments, ensuring reliable and reproducible results.

Recirculating Chillers

Chillers are widely employed in advanced composites manufacturing processes. They use refrigeration technology to remove heat from the system and maintain the desired temperature. Recirculating chillers offer several benefits in advanced composites research and production processes, including:

Precise temperature control:

• Advanced composites often require precise temperature control during curing, moulding, or other manufacturing processes. Recirculating chillers provide accurate and stable temperature control, ensuring that the composite materials cure or solidify under optimal conditions. The ability to maintain a consistent temperature profile throughout the process helps to achieve uniform material properties and minimises the risk of defects.

Efficient heat dissipation:

• Advanced composites processes generate heat during curing or moulding due to exothermic reactions. Recirculating chillers effectively dissipate the excess heat, preventing overheating and ensuring the integrity of the composite material. The efficient heat dissipation capability of recirculating chillers helps to maintain process stability, reduces the risk of thermal damage, and improves the overall quality of the final product.

Wide temperature range:

• Recirculating chillers offer a wide temperature range, allowing researchers and manufacturers to control the process temperature according to the specific requirements of advanced composites. Different composite materials and manufacturing processes may demand specific temperature profiles. Recirculating chillers provide the flexibility to achieve and maintain the desired temperature range, enabling the optimisation of material properties and process parameters.

Ease of use and maintenance:

• Recirculating chillers are designed to be user-friendly, with intuitive controls and interfaces for easy operation. They often come with built-in safety features, alarms, and system diagnostics, ensuring reliable and hassle-free operation. Maintenance requirements are typically minimal, and routine tasks such as filter changes and fluid refills can be easily performed. The user-friendly nature and low maintenance needs of recirculating chillers contribute to the efficiency and productivity of advanced composites research and production processes.

Process optimisation:

• The precise temperature control provided by recirculating chillers allows researchers and manufacturers to optimise advanced composites processes. Fine-tuning the temperature parameters can lead to improved material properties, enhanced curing kinetics, and better control over the manufacturing process. Recirculating chillers enable researchers to explore different temperature profiles and optimise the composite material’s performance and characteristics.

Compatibility with process equipment:

• Recirculating chillers are designed to be compatible with various process equipment used in advanced composites research and production. They can be seamlessly integrated into the setup, such as moulds, curing chambers, or other process equipment. This compatibility ensures efficient cooling across the entire process, facilitating reliable and consistent results.

 

Heat Exchangers

Heat exchangers play a vital role in advanced composites processes by facilitating efficient heat transfer. They enable the exchange of heat between the cooling fluid and the process fluid, offering comparable advantages to a recirculating chiller. However, heat exchangers come with the added benefits of lower initial cost and reduced energy consumption. These factors contribute to efficient heat transfer, precise temperature control, and ultimately enhance the overall quality of advanced composites. Some of the benefits provided by heat exchangers in advanced composites research and production include:

Efficient heat transfer:

• Heat exchangers are designed to facilitate efficient heat transfer between two fluids, typically the process fluid and a heat transfer fluid. In advanced composites processes, heat exchangers efficiently remove excess heat generated during curing or moulding, helping to maintain the desired temperature range. By rapidly and effectively dissipating heat, heat exchangers prevent overheating, minimise thermal damage, and ensure the structural integrity and quality of the composite material.

Efficient heat dissipation:

• Heat exchangers efficiently remove excess heat generated during the graphene synthesis process. CVD processes, for example, involve the decomposition of carbon-generation. Heat exchangers facilitate efficient cooling, preventing overheating and minimising thermal gradients across the graphene layers.

Temperature control:

• Heat exchangers allow temperature control in advanced composite processes. By removing heat from the process fluid, they help to regulate the temperature within the desired range. Heat exchangers contribute to temperature stability, ensuring consistent curing conditions throughout the process. This control and stability results in uniform material properties, reduced variability, and improved overall product quality.

Process efficiency and productivity:

• The efficient heat transfer provided by heat exchangers contributes to improved process efficiency and productivity in advanced composites manufacturing. By quickly removing excess heat, heat exchangers reduce curing or moulding cycle times, allowing for faster production. This enhanced efficiency helps to increase throughput, reduce energy consumption, and optimise overall process performance.

Customisation and adaptability:

• Heat exchangers can be customised and adapted to specific process requirements. They can be designed and engineered to fit the unique needs of advanced composites research and production setups. Heat exchangers can be integrated into existing process equipment, moulds, or curing chambers, allowing for seamless operation and efficient cooling. This customisation ensures that the heat exchangers are optimised for the specific process parameters, resulting in improved performance and tailored solutions.

Scalability:

• Heat exchangers are available in various sizes and configurations, allowing for scalability in advanced composites research and production. They can be employed in laboratory-scale research or scaled up for industrial production. The scalability of heat exchangers ensures consistent and reliable heat transfer across different volumes and production scales, accommodating diverse manufacturing requirements.

Cost-effectiveness:

• Heat exchangers offer cost-effectiveness in advanced composites research and production processes. They provide an efficient means of heat removal without the need for continuous energy input. Heat exchangers can be designed for optimal energy efficiency, reducing operational costs in the long run. Additionally, heat exchangers minimise the risk of thermal damage to the composite material, resulting in cost savings associated with minimising waste and rejected parts.

 

It's important to note that the specific cooling equipment used may vary depending on the process requirements, facility infrastructure, and budget constraints. The selection and design of process cooling systems are often customised to meet the unique needs of advanced composites research and production.

We are excited to be exhibiting at Advanced Materials 2023. Find us on stand 1418 for a chat about how we can support with your process cooling requirements.