An Introduction to the Use of Life Cycle Assessment in Machining

In today's globalized economy, growing concern exists regarding the tradeoff between economic growth and respect for the environment. This conflict is not alien to companies; as many have started to include environmental sustainability in addition to their usual objectives of profitability and efficiency. The manufacturing industry is a major contributor to the overexploitation of resources and to environmental pollution through the generation, accumulation or improper disposal of waste and greenhouse gas emissions. In this context, machining is one of the main processes in manufacturing. Its intrinsic characteristics make it an intensive process regarding energy, water consumption, and waste generation. In addition, cutting tools suffer from high wear rates that result in high tool consumption and, thus, a high environmental footprint. Life Cycle Assessment (LCA) is the most widely used methodology for assessing the environmental impacts of manufactured products. It has also been used in machining because it allows a holistic approach that encompasses all environmental exchanges of a product or process throughout its life cycle. Particularly, it allows comparing scenarios when a proper baseline is established to select more environmentally friendly ones. However, comparisons among setups that include, for instance, different workpiece materials are hardly helpful due to the influence of machinability on the process. The present study is aimed at introducing LCA into machining. It provides an overview of relevant studies in which the LCA framework was applied to machining and other manufacturing processes.