A methodology for the environmental comparison of metal shaping technologies: an in-depth analysis on recycling related issues

The reduction of CO2 emissions is an urgent objective to pursue. The scientific and the industrial world have gathered such challenge, starting to find out energy- and resource-efficient manufacturing strategies. From the literature review, in the domain of environmental impact analysis of manufacturing processes, two relevant knowledge gaps can be spotted: (1) the metal forming processes (and, in particular, the bulk forming processes) are still not well documented, and (2) there is a lack of systematic and comparative studies on energy and material flows enabling the identification of environmentally-friendly manufacturing design strategies. This research offers a contribution to a better understanding of the environmental impact of forming and machining processes. The performance of the two processes is evaluated and compared with the varying of the material usage related factors. The impacts on the final results of the aluminum recycling strategy as well as of the applied method to account for benefits of recycling are analyzed. Therefore, the paper represents an effort aimed at tuning and improving a methodology able to thoroughly analyze the environmental impact of a given process, and to better compare different manufacturing strategies from the environmental point of view.