Periodic Reporting for period 1 - MULTHEM (Multi-material additive manufacturing for lightweight and thermal management)
Período documentado: 2022-12-01 hasta 2024-05-31
The 26th Climate Change Conference has highlighted the urgent need to reduce global carbon dioxide emissions to limit global warming. The transport sector accounts for approx. 16% of the global carbon emissions and has identified fleet
electrification as the primary route to achieving climate neutrality. However, the main challenges are the current weight of components and the cost of new systems to ensure efficiency and long-term sustainability. As a result, the industry
has recognized the need for transformative technologies and production methods to develop lighter, more efficient, and cost-effective solutions to enable this transition and achieve climate neutrality. With their outstanding mechanical strength, Carbon Fibre Composites (CFCs) have been increasingly used to replace metals in products requiring lightweight features, such as aircraft or high-performance vehicles. However, due to the traditional manufacturing process and poor thermal conductivity, the use of CFC has been limited to structural applications. For example, batteries, electrical motors, and power electronics, where power losses need to be efficiently dissipated, typically require separate heat exchangers, resulting in heavier and less cost-effective solutions that still utilize bulky designs and heavy materials. The vision of MULTHEM is to develop a reliable and validated Additively Manufactured (AM) CFC process with enhanced thermal conductivity with different material combinations and nanotechnology. This innovative approach will allow the development of components, such as battery and motor housings with dual functionality comprising structural and cooling features and with a more cost-effective approach than traditional methods. This solution will enhance the product performance, first by the weight reduction achieved by designs that only AM enables, and second, by using CFC-metal structures with enhanced thermal conductivity strategies, lighter and stronger than aluminum or steel.
electrification as the primary route to achieving climate neutrality. However, the main challenges are the current weight of components and the cost of new systems to ensure efficiency and long-term sustainability. As a result, the industry
has recognized the need for transformative technologies and production methods to develop lighter, more efficient, and cost-effective solutions to enable this transition and achieve climate neutrality. With their outstanding mechanical strength, Carbon Fibre Composites (CFCs) have been increasingly used to replace metals in products requiring lightweight features, such as aircraft or high-performance vehicles. However, due to the traditional manufacturing process and poor thermal conductivity, the use of CFC has been limited to structural applications. For example, batteries, electrical motors, and power electronics, where power losses need to be efficiently dissipated, typically require separate heat exchangers, resulting in heavier and less cost-effective solutions that still utilize bulky designs and heavy materials. The vision of MULTHEM is to develop a reliable and validated Additively Manufactured (AM) CFC process with enhanced thermal conductivity with different material combinations and nanotechnology. This innovative approach will allow the development of components, such as battery and motor housings with dual functionality comprising structural and cooling features and with a more cost-effective approach than traditional methods. This solution will enhance the product performance, first by the weight reduction achieved by designs that only AM enables, and second, by using CFC-metal structures with enhanced thermal conductivity strategies, lighter and stronger than aluminum or steel.
The MULTHEM project is developing multi-material additive manufacturing for lightweight and thermal management by employing the benefits from metals, Carbon Fibre-Reinforced Polymers (CFRP) and additive manufacturing. The MULTHEM project has been working on WP2 to develop different polymer-metal composites by Material Extrusion (MEX) and metal combinations by Laser Metal Deposition (LMD-powder and LMD-wire) technologies. Moreover, the different reinforced polymers and metals developed under WP2 have been joined by Electron Beam, Laser Beam and Friction Stir welding technologies under WP3. MEX additive manufacturing technologies are being used to manufacture new composites, and thermoplastics with a reinforcement of short and continuous carbon fibres. Some KPIs have been already achieved during the M1-M18 period: i) 4 different polymer composites (PA6-sCF, PEKK-sCF, PA6-CCF and PEKK-CCF) have been developed by MEX in the same process (at least 2 were the target number), ii) Mex overprinting is currently being investigated, iii) 2 aluminium alloys (Al5356 and AlSi7Mg) have been developed by LMD-wire and LMD-powder (at least 2 was the target number), and iv) 2 different polymer-metal composites (PA6-sCF/AlSi10Mg and PEKK-sCF/AlSi10Mg) have been investigated during M1-M18 period by three different welding technologies -EBW, LBW and R-FSW- (at least 2 polymer-metal composites were the target number).
The project is developing polymers reinforced with continuous fibres which allows the production of thin, light yet strong specimens. These fibres can be placed only where the reinforcement is needed, thus minimizing the structural mass. The drawback of using only polymer-based materials is the poor heat transfer capability. In this sense, aluminium lightweight structures are also being manufactured. Therefore, lightweight structures with heat dissipation to prevent loss of performance of electric devices are under investigation.
An intensive work on re-design and simulation of the mechanical and thermal behaviour is being conducted. Optimized housing designs are being developed. A comparison against the traditional housing manufacturing approach and results of the investigation of thermal, electrical and mechanical performance of the new multilateral approach is the main core of the work carried out in WP6. Electromagnetic, mechanical and thermal FEA analyses have been conducted for the electrical motor to establish a baseline performance after comparing these values with those obtained for the MULTHEM technology. Regarding the battery casing for an E-bike, simulation studies on the thermal and impact performance have been done. Re-design and simulation with multi-material approaches employing the material properties from WP2 are also ongoing.
The project is developing polymers reinforced with continuous fibres which allows the production of thin, light yet strong specimens. These fibres can be placed only where the reinforcement is needed, thus minimizing the structural mass. The drawback of using only polymer-based materials is the poor heat transfer capability. In this sense, aluminium lightweight structures are also being manufactured. Therefore, lightweight structures with heat dissipation to prevent loss of performance of electric devices are under investigation.
An intensive work on re-design and simulation of the mechanical and thermal behaviour is being conducted. Optimized housing designs are being developed. A comparison against the traditional housing manufacturing approach and results of the investigation of thermal, electrical and mechanical performance of the new multilateral approach is the main core of the work carried out in WP6. Electromagnetic, mechanical and thermal FEA analyses have been conducted for the electrical motor to establish a baseline performance after comparing these values with those obtained for the MULTHEM technology. Regarding the battery casing for an E-bike, simulation studies on the thermal and impact performance have been done. Re-design and simulation with multi-material approaches employing the material properties from WP2 are also ongoing.
WP2: The materials selected are commercial since there is a need for a large quantity of materials to build the use cases. Before this project, the selected AM methods had yet to process some of the materials selected, and the establishment of the AM methodology represents a step beyond the state of the art. For example, the literature has yet to report material extrusion additive manufacturing of PEKK with continuous carbon fibre (PEKK-CCF); thus, it represents a breakthrough since this type of composite offers significantly higher thermal and mechanical performance, which the aeronautical industry requires. In addition, the complete mechanical and thermal characterization of PEKK-CCF is also a step beyond the state of the art and will allow the design of more efficient lightweight housings for electronic and electric devices. The development of the CFD model for LMD-wire is also a result beyond the state-of-the-art since commercial software is only available for PBF. The process parameters developed for the Al5356 by LMD-wire (in an M450 device) are also results beyond the state-of-the-art since this model of AM technology has a low-energy source and the processing of aluminium alloys is difficult due to big porosity and lack-of-fusion problems.