Development of a Comparative Assessment Method For Additive and Conventional Manufacturing With Regard to Global Warming Potential

Abstract

Additive Manufacturing (AM) opens new possibilities for producing complex parts while achieving high material efficiency. Besides the technological advantages, AM is considered a key technology for sustainable production. A widely used approach to measure the sustainability of a product is the Life Cycle Assessment (LCA) by using the impact category of the Global Warming Potential (GWP). The setup of LCA is complex and requires a deep understanding of the process. LCAs carried out so far for AM mainly focused on energy consumption and the printing process itself. GWP caused by other up and downstream manufacturing steps, such as material preparation, has received little attention so far. This requires more comprehensive LCAs, increasing the complexity and effort. Therefore, the GWP is often not considered when deciding whether to use AM or Conventional Manufacturing (CM) for producing a part in the industry. This work presents a simplified method (GWP-method) for comparing AM and CM regarding the GWP by identifying so-called hotspots (the most significant production steps in terms of GWP). Based on the identified hotspots, the assessment scope was narrowed down, and an Assessment Equation (GWPAE) was developed. The GWPAE can then be used for the analysis of produced GWP for other product families and production scenarios for the defined process route. The method is demonstrated for an aerospace part as a case study. Finally, the deviation of the derived GWPAE is checked by directly comparing the results of the GWP of an LCA for another production scenario and lies at 5,9%.