Design optimization of lightweight automotive seatback through additive manufacturing compression overmolding of metal polymer composites

• Published in: Composite structures 2024-12, Vol.349-350, p.118504, Article 118504
• Main Authors: Pokkalla, Deepak Kumar, Garg, Nikhil, Paramanathan, Mithulan, Kumar, Vipin, Rencheck, Mitchell L., Nandwana, Peeyush, Kunc, Vlastimil, Hassen, Ahmed Arabi, Kim, Seokpum
• Format: Article
• Language: English
• Subjects: Binder jet additive manufacturing; Compression molding; Finite element analysis; Large-scale additive manufacturing; MATERIALS SCIENCE; Metal polymer composites; Structural optimization
• ISSN: 0263-8223
• DOI: 10.1016/j.compstruct.2024.118504

With the growing demand for enhanced automotive fuel efficiency and environmental sustainability, there is a need for lightweighting automotive components through innovative design and manufacturing processes. This study leverages a combination of numerical iterative design optimization and hybrid additive manufacturing–compression molding (AM-CM) technique for metal polymer composites to lightweight an automotive seatback. The AM-CM process enables robust mechanical interlocking between metals and composites, boasting high stiffness and strength with low overall density. Replacing metallic components with such metal polymer composites allows for comparable mechanical performance while significantly reducing the overall weight. First, the automotive seatback design space is reduced to critical load carrying regions using topology optimization and high stress concentration areas are identified using finite element analysis. Next, a lightweight metal polymer subcomponent is designed for a high stress concentration region. The full seatback frame with spatially heterogeneous material-specific design is then iteratively optimized to enable enhanced stiffness with minimal weight. Overall, the automotive seatback frame designed with location-specific metal, polymer, and metal polymer composite materials weighs 20% less than the metal-only design while exhibiting similar stiffness. [Display omitted] •Additive manufacturing–compression molding cut seatback weight by 20% with better stiffness.•Topology optimization reduces seatback design to critical load carrying regions.•New metal insert design enables adhesive-free mechanical interlocking in hybrid composites.•Feasibility of metal insert design shown by fabricating metal–polymer composite.