Energy efficiency analysis for machining magnesium metal matrix composites using in-house developed hybrid machining facilities

Abstract

Adoption of sustainable machining techniques shall offer the local industry a cost-effective route to improve its environmental, economic and social footprint when it comes to machine difficult-to-cut materials. This experimental study investigates the behavior of sustainable cutting fluid approaches on active cutting energy (ACE), active energy consumed by machine tool (AECM) and energy efficiency (EE) for machining PMMCs (particulate metal matrix composites) of magnesium at different combinations of rotational speed and feed. Minimum Quantity Lubrication (MQL), cryogenic and CryoMQL machining are performed on in-house developed MQL and cryogenic experimental setups and the results obtained from them are compared with dry machining. The L36 orthogonal array is employed to design the experiments. It is observed that cryogenic machining consumes comparatively lower ACE and AECM among the four cutting fluid approaches. It is found that dry machining provides comparatively lower EE among four cutting fluid approaches. From the main effects plot, it is observed that cryogenic assistance further improves the machining performance of the MQL technique and offers better EE. The results of Analysis of Variance (ANOVA) suggest that rotational speed, cutting fluid approach and feed are the significant parameters that affect the EE in descending order respectively.