Ökobilanzielle Bewertung einer additiven und einer konventionellen Fertigungsroute

This paper examines the cumulative environmental impact of two technologically distinct manufacturing routes for a component made of corrosion-resistant steel, taking into account the relevant standards as far as possible. The motivation for this investigation is the growing importance of understanding and assessing industrial production processes and their process chains in terms of energy demand and emission profiles against the backdrop of rising expectations regarding resource efficiency and climate protection. In view of the divergent findings in the literature on the ecological performance of metallic additive manufacturing, there is a need for a methodologically clearly defined comparison with a conventional route. The modelled life cycle assessment covers the material, manufacturing, and transport phases of both routes and was carried out using the ANSYS Granta Eco Audit Tool on the basis of the program¿s material data sets, supplemented where necessary by literature sources. To ensure comparability and to evaluate the ecological impacts of the isolated process chains, the same finished component mass is used for both routes; design-related, topology-optimising weight reductions that could potentially be realised in additive manufacturing are deliberately not considered. Ultimately, the two indicators of cumulative energy demand and emissions were assessed using a cradle-to-gate approach. The analysed scenario favoured the conventional route, which shows a considerably lower environmental impact, with a cumulative energy requirement of roughly 800 MJ and carbon dioxide emissions of about 65 kg. In contrast, the key figures for the additive route were approximately 1700 MJ and around 140 kg of emissions, roughly twice as high as for the conventional process. Moreover, the results indicate marked differences in the dominant impact drivers: while the conventional route is shaped largely by the material phase, the additive route is almost entirely determined by the energy consumption of selective laser melting. Transport contributes only marginally. The analysis shows that the results depend primarily on the chosen methodological framework, the defined system boundaries, but also on underlying assumptions, in particular the energy requirements and electricity mix of the individual process modules. The work thus creates a comprehensible basis for comparing the ecological performance of additive and conventional manufacturing routes. Further investigations should take into account real energy profiles and measurement data from industrial plants and extend the system boundaries to include usage and end-of-life phases.