I News
For the lightweight development of electric vehicles, not only appropriate lightweight solutions are needed, but also cost-effectiveness and sustainability throughout the life cycle. The Enlight project (Enhanced Lightweight Design), in which the School of Automotive Engineering of RWTH Aachen University in Germany participates, is committed to developing modular components and promoting the lightweighting of electric vehicles through the mixed application of a series of innovative materials and process technologies. It is planned to achieve the application of large-scale electric vehicles (EVs) from 2020 to 2025. The Enlight project focuses on the development of composite materials based on thermoplastic and thermosetting resin matrices, and develops modular electric vehicle components through multi-material enhanced design. Including: front-end modules, floor structures, doors, crossbeams and chassis control arms. In addition, Enlight also includes advanced technologies such as modular design, performance simulation, and experimental simulation. The School of Automotive Engineering of RWTH Aachen University is mainly involved in the design, simulation and testing of all body components. For the components of the front end of the vehicle, while reducing weight, it is also necessary to focus on its collision strength and energy absorption. Therefore, the project chose a mixed design of metal and plastic parts. Considering sustainable development, the bio-based high-performance polyamide Eco-PaXX (PA410) material was selected as the substrate. The material has high mechanical properties, high chemical and heat resistance, and is environmentally friendly. In addition, it has low moisture absorption compared to other thermoplastic materials. The plastic parts are made of high-content continuous carbon fiber reinforced Eco-Pa composite materials.
The collision system consists of an aluminum crash box and a hybrid bumper beam, as shown in Figure 1 (a). The bumper beam is made of aluminum profiles, and the outer panel reinforcement is made of carbon fiber reinforced composite materials. The mechanical properties of the carbon fiber composite outer panel are further improved by optimizing material thickness, fiber layer design, and short fiber skeleton design. The manufacturing process involves (non-metallic materials) hot forming, overmolding, Organomelt process, SpriForm process, and FiberForm process. In terms of connection, the beam and the crash box are spot welded, and the connection between the crash box and the trailer hook is MIG welding.
The longitudinal beam is directly installed on the crash box by bolting, forming a traditional load path under frontal collision conditions. As shown in Figure 1 (b), the carbon fiber composite crash energy absorption tube is placed inside the aluminum profile, and the front and rear ends are connected to the deflector plate, and the position of the crash tube is fixed by the deflector plate. The energy absorption tube is connected to the deflector plate by adhesive, and the deflector plate is connected to the aluminum profile by MIG welding. Then the entire hybrid component is installed on the front crash box by screws. The higher ductility of aluminum alloy ensures the integrity of the front structure during the collision, while CFRP provides better energy absorption capacity. For the composite crash tube, the fiber is continuously wound at different angles and then composited. Tests show that its axial energy absorption effect is better between 0° and 15°. Considering the longitudinal energy absorption and manufacturability, the fiber angle of +10°/-10° is selected for winding.
The rear connecting plate of the front longitudinal beam is one of the main load-bearing components in the frontal collision situation. It receives the load from the front longitudinal member and disperses the load to the door sill, floor and firewall. In addition, the rear connecting plate of the front longitudinal beam serves as a supporting structure for the chassis and powertrain components, and its design is shown in Figure 2 (b). It consists of two hot-formed CFRP parts, the upper and lower shells, connected at the flange to form a closed geometry. Plastic parts are usually connected by bonding or riveting, but this part uses plastic welding technology. The front end of the corner node is supported by aluminum reinforcements to stabilize the deflector plate. The chassis and engine bracket mounting points are made of steel and connected to the corner nodes by adhesive and SPR.
The collision system consists of an aluminum crash box and a hybrid bumper beam, as shown in Figure 1 (a). The bumper beam is made of aluminum profiles, and the outer panel reinforcement is made of carbon fiber reinforced composite materials. The mechanical properties of the carbon fiber composite outer panel are further improved by optimizing material thickness, fiber layer design, and short fiber skeleton design. The manufacturing process involves (non-metallic materials) hot forming, overmolding, Organomelt process, SpriForm process, and FiberForm process. In terms of connection, the beam and the crash box are spot welded, and the connection between the crash box and the trailer hook is MIG welding.
The longitudinal beam is directly installed on the crash box by bolting, forming a traditional load path under frontal collision conditions. As shown in Figure 1 (b), the carbon fiber composite crash energy absorption tube is placed inside the aluminum profile, and the front and rear ends are connected to the deflector plate, and the position of the crash tube is fixed by the deflector plate. The energy absorption tube is connected to the deflector plate by adhesive, and the deflector plate is connected to the aluminum profile by MIG welding. Then the entire hybrid component is installed on the front crash box by screws. The higher ductility of aluminum alloy ensures the integrity of the front structure during the collision, while CFRP provides better energy absorption capacity. For the composite crash tube, the fiber is continuously wound at different angles and then composited. Tests show that its axial energy absorption effect is better between 0° and 15°. Considering the longitudinal energy absorption and manufacturability, the fiber angle of +10°/-10° is selected for winding.
The rear connecting plate of the front longitudinal beam is one of the main load-bearing components in the frontal collision situation. It receives the load from the front longitudinal member and disperses the load to the door sill, floor and firewall. In addition, the rear connecting plate of the front longitudinal beam serves as a supporting structure for the chassis and powertrain components, and its design is shown in Figure 2 (b). It consists of two hot-formed CFRP parts, the upper and lower shells, connected at the flange to form a closed geometry. Plastic parts are usually connected by bonding or riveting, but this part uses plastic welding technology. The front end of the corner node is supported by aluminum reinforcements to stabilize the deflector plate. The chassis and engine bracket mounting points are made of steel and connected to the corner nodes by adhesive and SPR.