Application of Automotive Closure Parts with Multi-Material Design Concept

The automotive industry is changing rapidly with the electrification of vehicle powertrains. Many EV platforms have emerged, and the safety issues of battery-pack structures are being studied. The goal of vehicle design is a reasonable compromise between weight reduction and vehicle cost without decreasing vehicle performance or safety. Reducing the impact on global warming is another concern. Automotive industries are making efforts to confront this situation, one of which is using multi-material structures for vehicle bodies. Automotive closure parts account for more than 15% of the total vehicle body weight and have many different components. Therefore, efforts have been made to optimize the structure and material to reduce weight. However, applying different materials to automotive closure parts presents several technical challenges. The combination of dissimilar materials is vulnerable to corrosion, and distortion may occur after the painting process due to the different thermal responses of the materials. From a manufacturing perspective, the use of multi-materials can cause problems in the production line (process conformity). Thus, adaptive solutions to produce closure parts made of multi-materials are needed. This study addressed the design of multi-material closure parts and related manufacturing process issues, such as forming, assembling, corrosion resistance, and dimensional accuracy.