Chip morphology and tool wear investigation in high-speed machining of AZ61 magnesium alloys using vegetable-oil based cutting fluid

Abstract

ABSTRACT Lightweight alloys play a vital role in the development of automotive, biomedical and aerospace industries as well as other industrial sectors. The current study investigates the machinability of AZ61 magnesium alloy within a vegetable-oil-based MQL environment through high-speed orthogonal cutting. A tool wear and chip morphology examination are conducted along a full factorial experimentation to allow for adequate machinability testing. The usage of Grey Relational Analysis was invoked to allow for a multi-variant optimisation of input parameters such as MQL flow rate, cutting speed, and feed based on output responses, such as chip compression ratio, chip segmentation ratio, tool-chip contact length, and shear angle as well as tool wear evolution. Through the analysis of the formulated signal-to-noise data, it was found that the optimal cutting parameters were an MQL flow rate of 80 ml/h, cutting speed of 250 m/min and feed of 0.3 mm/rev. The optimal cutting conditions resulted in a Grey Relational Grade improvement of 0.177 as compared to the referenced experimental trail. The analysis of variance further concluded that the feed was the highest contributing input parameter at 38.04% followed by the MQL flow rate and the cutting speed.