Manufacturing energy and environmental evaluation of metallic sheets reshaping based on theoretical models and cradle-to-gate assessment

Abstract

Origami sheet metal folding (OSM) is a cutting-edge method for forming a 3D sheet metal product employing a series of folding procedures from a 2-D flat metal sheet rather than using the conventional stamping process. OSM eliminates the need for presses and considerable energy usage during manufacturing by solely using a sequence of bends to shape the necessary geometry. OSM has the potential to supplant the current stamping method and be a disruptive fabrication process for metal manufacturing. Despite OSM's potential, there is not enough analysis to assess the OSM approach in terms of its energy efficiency and emission. Therefore, the added value of this study is to highlight the application of OSM in sheet metal folding and present the key distinctions between this method and stamping in the various production phases, including primary production, processing, manufacturing, and assembly. In order to assess the applicability of this approach and its merits compared to the conventional methods, an extensive analysis of its environmental impacts (energy consumption and CO2 emission) using theoretical models and the Life Cycle Analysis (LCA) was also carried out. A case study was presented for analyzing a floor panel of the vehicle with the derived theoretical model and LCA inventory data. The theoretical model for manufacturing energy of OSM was adopted from mathematical models for the CO2 laser cutting process to estimate the energy for laser cutting. Alternatively, the model considered a mathematical approximation developed for coated sheet steel to estimate the total energy consumed for OSM. Finite element analysis (FEA) was also used to generate a more precise energy estimate using a vehicle floor panel as a case study. The highlighted environmental impacts of OSM, including energy consumption and carbon emission, were finally compared to stamping. The results of the investigation revealed that the primary distinction between OSM and stamping methods is at the manufacturing phase. The use of the OSM approach significantly reduced energy consumption and carbon dioxide emissions during the production of metal-based components by ∼94% and ∼92%, respectively. It can be concluded that OSM saves significant energy and produces fewer emissions than the stamping process and can be a potential candidate for sheet metal folding.