Present and Future Sustainability Development of 3D Metal Printing

Abstract

Additive manufacturing (AM), also known as 3D printing is a relatively new concept and promising technology for industrial production. It is important to investigate the environmental impact of the AM process in light of the critical situation of the Earth. The elimination of some costly prefabrication processes such as molding or post-fabrication stages such as machining and welding required in traditional manufacturing methods favor the AM process and provide great economic advantages. Furthermore, the reduction of manufacturing steps contributes to environmental protection through fewer operations, less material, and energy consumption, and reduced transportation. This study is a preliminary work for analyses of environmental impact and life cycle of some well-known AM technologies for manufacturing metallic parts and components. As a case study, fabrication of a pump impeller is simulated through a well-known metal production AM technology and a conventional technology such as a casting process for direct comparison. Life Cycle Analysis (LCA) is applied to measure the environmental impact in five different stages of pump impeller lifetime with the two different fabrication processes. AM compared to casting has an environmental impact reduction of 15%, 20%, 65%, 20%, and 10% respectively in Global Warming Potential (GWP), Acidifications Potential (AP), Water Aquatic Eco-toxicity Potential (FAETP), Human Toxicity Potential (HTP), and Stratospheric Ozone Depletion (ODP). In the pre-manufacturing stage, the AM process has a higher impact on the environment in comparison with the casting process due to intense electricity consumption. Using hydroelectricity and renewable energy electricity mitigates the environmental impact of the AM process in pre-manufacturing and manufacturing stages as temporary until the advancement of AM technology for consuming less energy. Finally, a plan for future research to enhance the environmental sustainability of the AM process is proposed.