A Case Study: Design of an Automotive Seat Backrest by Carbon Fiber Reinforced Plastics

Abstract

The current automotive seats are mainly manufactured by steel that increases the vehicle weights, fuel consumption and CO2 emissions, and hence, lightweight carbon fiber-reinforced polymer (CFRP) will be a prospective substitute material. The integrated design method of a CFRP seat backrest will be studied and verified numerically. On the condition that the unchangeable seat dimensions and previous mounting positions on the floor, a three-dimensional CAD conceptual model in which the design and non-design domains were separated was established firstly, and then, the optimal material distribution in the design domain was determined by topology optimization technology according to the ECE (European Union standards) test standard. Next, the positions of ribs are determined and the manufacturing feasibility was verified numerically. Finally, the finite element model of the CFRP seat backrest was established, and static bending stiffness and crashworthiness were analyzed and the simulation results were compared with the previous all-steel structure. It is demonstrated that a 20.4% weight reduction is achieved, and previous 26 steel components could be replaced by only one CFRP component and no additional assembly is required. Both the static and impact test standards are satisfied.