Trends in Lightweighting for Automotive Applications: A Case Study

Abstract

Roughly 25% of all energy-related greenhouse gas emissions (GHG) are attributable to the transportation sector, which accelerates global warming. Vehicle lightweighting and GHG emissions are intrinsically correlated. This paper reviews the advances in lightweight materials, particularly advanced high-strength steel, reinforced composites, aluminum, magnesium, and titanium alloys. The challenges limiting the mass adoption of vehicle lightweighting, including material production energies, vehicle operational efficiencies, and other substitution factors such as life-cycle analysis, environmental impacts, manufacturability, cost-effectiveness, crashworthiness, and recyclability, are highlighted. Emerging state-of-the-art techniques such as design for additive manufacturing (DfAM), multi-scale modeling of materials, multi-material design, bionic-inspired designs, and Industry 4.0 in vehicle lightweighting are also explored. The paper details an experimental case study on material substitution of a steel vehicle door hinge with aluminum alloy (A6061-RAM2). A weight reduction of 66% was realized. Selective laser melting (SLM) was used to fabricate the aluminum hinge samples. The samples did not fracture when a transverse load of 4500 N and a longitudinal load of 5500 N were applied bi-directionally from the X and Y axes of the vehicle, respectively.