On a Process Modeling Framework for Sustainable Manufacturing: A Machining Perspective

Sustainability and economic factors are increasingly pushing industry towards environmentally friendly manufacturing methods. However, the implications of processing level changes, which are being introduced at a significant rate, for overall, environmental impact need better characterization. In the first half of this paper, a simplified framework for enhancing sustainability in manufacturing, by enabling rapid assessment of approximate life-cycle implications of competing process-level alternatives, is introduced. This framework relies on developing or enhancing manufacturing process models in such a way that a superior quantitative evaluation of the environmental and economic impacts of decisions made in manufacturing process planning can be established. In the second half of this paper, the specific case of metal machining is presented. In machining the maximum attention has been directed towards reducing the traditional profligate use of metalworking fluids. Consequently, a significant quantity of research work has been directed towards developing dry and near-dry, or Minimal Quantity Lubrication (MQL), machining techniques. A review of available literature shows that several outcomes of these techniques for product life-cycle assessment need to be addressed — i.e., some environmental tradeoffs are often involved in their implementation. Avenues for further research in sustainable machining, including some ideas for advancing dry and near-dry machining without resorting to chemical action for extreme-pressure lubrication, are also presented.