Surface roughness in al 7075-t6 using shoulder mill cutter by response surface methodology

The present experimental work investigated the effects of cutting parameters on surface roughness in shoulder milling of AL7075-T6 aluminium alloy using a coated solid carbide cutter. Response surface methodology was used to develop a mathematical model to predict surface roughness in terms of cutting speed, feed rate, depth of cut. The objective of this study was to develop a better understanding of the effects of spindle speed, feed rate and depth of cut on the surface roughness then to build a multiple regression model. Such an understanding could provide insight into the problems of controlling the finish of machined surfaces when the process parameters were adjusted to obtain a certain surface finish. Surface roughness value was measured using Mitutoyo Surf test SJ201tester. The adequacy of the model was verified using analysis of variance (ANOVA), and the effect of spindle speed (Vc), feed rate (fz) and depth of cut (ap), and interactions of all variables predicted the surface roughness values within the confidence limit. The deviation between predicted and measured surface roughness values was within an error band of about 5 per cent. The contour plots were generated to study the effect of process parameters as well as their interactions.