Summary: Impellers are the core components of turbomachinery in petrochemical and aeronautical engineering. In addition to conventional manufacturing (CM), additive manufacturing (AM) and remanufacturing (RM) can also be used in impeller production. This article presents a life cycle assessment method comparing the environmental impacts of different impeller manufacturing methods, including plunge milling (CM), laser cladding forming (AM combined with CM), and additive remanufacturing (RM). Results show that RM is the most environmentally favorable option, followed by AM and CM, in terms of global warming potential (GWP), Chinese resource depletion potential (CADP), water eutrophication potential (EP), and acidification potential. However, AM is not always more environmentally friendly than CM. The comparison of impeller production by CM and pure AM, in this case, indicates that the environmental burden of production using pure AM is approximately twice than that of CM. Compared with CM, the RM of impellers would reduce GWP, CADP, and EP by 64.7%, 66.1%, and 75.4%, respectively. The results of this study contribute to a scientific basis for the selection of manufacturing methods and the sustainable manufacturing of impeller production enterprises.

With the increasing awareness of environmental protection and sustainable manufacturing, the environmental impact of laser additive manufacturing (LAM) technology has been attracting more and more attention. Aiming to quantitatively analyze the energy consumption and extract possible ways to save energy during the LAM process, this investigation studies the effects of input variables including laser power, scanning speed, and powder feed rate on the overall energy consumption during the laser deposition processes. Considering microhardness as a standard quality, the energy consumption of unit deposition volume (ECUDV, in J/mm³) is proposed as a measure for the average applied energy of the fabricated metal part. The potential energy-saving benefits of the ultrasonic vibration–assisted laser engineering net shaping (LENS) process are also examined in this paper. The experimental results suggest that the theoretical and actual values of the energy consumption present different trends along with the same input variables. It is possible to reduce the energy consumption and, at the same time, maintain a good part quality and the optimal combination of the parameters referring to Inconel 718 as a material is laser power of 300 W, scanning speed of 8.47 mm/s and powder feed rate of 4 rpm. When the geometry shaping and microhardness are selected as evaluating criterions, American Iron and Steel Institute (AISI) 4140 powder will cause the largest energy consumption per unit volume. The ultrasonic vibration–assisted LENS process cannot only improve the clad quality, but can also decrease the energy consumption to a considerable extent.