A finite element design study and performance evaluation of an ultra-lightweight carbon fiber reinforced thermoplastic composite vehicle door assembly 2020-01-0203
The ever-growing concern to reduce the impact of transportation systems on environment has pushed automotive industry towards fuel efficient and sustainable solutions. While several approaches have been used to improve efficiency, the light-weighting of automobile components has proven broadly effective. A substantial effort is devoted to lightweight body in white which contributes ~35% of total weight of the vehicle. Closure systems, however, have been often overlooked. Closure systems are extremely important as they account for ~ 50 % of the structure mass and have a very diverse range of requirements including crash safety, durability, strength, fit, finish, NVH, and weather sealing. To this end a carbon fiber reinforced thermoplastic composite door is being designed to enable 42.5% weight reduction for an OEM’s mid-size SUV steel door. In this work, several novel composite door assembly designs are developed by using an integrated design, analysis and optimization approach. A design optimization is performed to satisfy static load case requirements which represent daily use and misuse. The crashworthiness of the door assembly is assessed by considering three non-linear load cases: (a) quasi-static pole test (FMVSS 214S) (b) full pole test (FMVSS 214) and (c) moving deformable barrier test (IIHS SI MDB). To evaluate the crash performance of the composite door designs, a set of key performance indicators listed by our OEM partner are assessed on a gauging metric. Furthermore, drape simulations are performed to assess the manufacturability of composite plies. It is concluded that ultra-lightweight thermoplastic reinforced composite door is a feasible design concept that is capable of satisfying all the design and performance requirements.