Energy Efficiency Assessment Using Material Removal Rate and Its Application to Wet and Dry End-Milling

Enhancing manufacturing sustainability has become more significant and urgent than ever before. In particular, energy demand for running machine tools greatly influences energy consumption in the manufacturing sector. As energy costs become expensive due to financial risks and political and national security risks, considering energy efficiency in manufacturing has become more important. Our previous work proposed an energy efficiency model based on specific energy consumption, indicating that a power function of the material removal rate represents energy efficiency as a performance measure. The model was examined solely in dry machining of aluminum alloys. In this study, we examine the effects of the material removal rate on energy efficiency in wet and dry machining of 12 types of metal materials. This study then demonstrates the capability of the proposed energy efficiency in machining by applying it to the assessment of energy efficiency between wet and dry end-milling processes. As a result, the proposed models can evaluate energy efficiency in machining under various conditions. Dry machining is advantageous to energy-efficient machining as the material removal rate increases.