International Journal of Engineering and Technology

Surface finish is a vital factor in the performance of finished components. Nose ball end milling is being extensively used for finishing of free form surfaces. Aluminium alloys like LM6 find increasing applications in automobile and aerospace industries. This paper presents an investigation of surface finish of LM6 Al alloy using ball nose end mill. Box Behnken approach of the Response Surface Methodology was selected for the design of experiments and mathematical modelling. The developed model was statistically validated using Analysis of Variance with R-squared value obtained at 92.42 %. Cutting speed and feed rate were found to be the most significant parameters. Machining parameters (cutting speed, feed and depth of cut) were optimised with consideration to surface roughness. The minimum optimised value of surface roughness predicted by GA was 0.45 microns (Ra). Validation experiments at optimal parametric settings showed an error of 8.88, which highlights the consistency of the developed model. Thus, this model helps manufacturers to select optimum settings for achieving desired surface quality of contoured finished products.