Investigation of the turning parameters on the surface finish of an aluminum bar

Abstract

The effect of parameters during turning such as spindle speed, feed rate, and depth of cut on the surface roughness was studied under dry and flood lubrication conditions. The turning process was performed on aluminum 6061 on a Lathe machine and optimised using Taguchi Orthogonal Array (OA) experimental method. The array used was L9. The turning operation used Tungsten Carbide as the cutting tool. Under flood lubrication, the cutting fluid used was Shell Dromus B, a soluble oil. The surface roughness was measured in terms of arithmetical mean value, Ra, using Mahr GD25 machine. Analysis was performed through mean S/N ratio and Analysis of Variance (ANOVA). It was found that the feed rate affects the surface roughness the most, with a contribution of 84% and 79% under dry and flood lubrication respectively, followed by spindle speed and depth of cut. There is a reduction of 27.2% in surface roughness when turning was performed under flood lubrication. The best combination of parameters to produce a good surface finish is by keeping a low feed rate with high spindle speed. The optimum turning condition was found when turning at spindle a speed of 1000 rpm, feed rate of 0.1 mm/rev, and depth of cut of 2 mm.