MULTI-OBJECTIVE OPTIMIZATION OF MACHINING PARAMETERS OF MILD STEEL AISI 1018 UNDER DRY AND COMPRESSED AIR-ASSISTED MACHINING

Abstract

In the machining process large amounts of heat are generated, and in order to remove them, it is necessary to utilize cutting fluids or adequate cooling agents, both of which are significant sources of waste production and detrimental to the environment. Due to these issues with cutting fluids, researchers were forced to develop novel methods, including dry machining, MQL, compressed air-assisted machining, and cryogenic machining. In this study, the key turning factors, such as cutting speed, feed rate, and tool overhang, were examined using the design of experiments to determine how they affected material removal rate and arithmetic average roughness (Ra) when turning AISI 1018 steel. Experiments were performed under dry cutting (DC) and compressed-air-assisted machining. Tests were designed according to Taguchi’s L9 orthogonal array. An ANOVA analysis was performed to determine the importance of machining parameters on the Ra and MRR using Minitab 18 software. Taguchi and an artificial neural network approach were used for output modeling. Finally, multi-objective optimization of the machining parameters was performed using Taguchi integrated with a genetic algorithm to minimize the surface roughness and maximize the material removal rate simultaneously using Mat lab R2019a. The findings showed that the material removal rate and roughness are significantly impacted by the cutting speed, followed by feed and tool overhang for dry and compressed air-assisted machining, respectively. Additionally, Taguchi models and artificial neural networks show strong correlations with experimental data. But artificial neural network models show more accuracy. The optimum machining parameters for multi-objective optimization during dry machining is Vc= 95.935 m/min, F = 0.104 mm/rev, and TOH = 40.024 mm, and the optimum result is MRR = 33.592 mm3 /sec and Ra = 1.443µm. Also, the optimum machining parameters during air assisted machining is Vc = 93.555 m/min, F = 0.1 mm/rev, and TOH = 41.701 mm, and the optimum result is MRR = 32.623 mm3 /sec, Ra = 0.468 µm.