Optimization of Machining Parameters for MRR and Surface Roughness for 7024 AL-alloy in Pocket Milling Process

Abstract

The objective of this work is the investigation of milling process variables which resulting in optimal values of the surface roughness and material removal rate during machining of 7024 Al-alloy. The machining operation implemented on C-TEK CNC milling machine. The effects of the selected parameters on the chosen characteristics have been accomplished using Taguchi’s parameter design approach; also ANOVA had been used to evaluate the contribution of each parameter on the process outputs. Different feed rates are used ranging from (60, 80 and 100) mm/min, found that high feed rates gives a high material removal rates and good surface roughness. On the other hand, using three levels of spindle speeds found that a higher spindle speeds gives better surface roughness with a little effect on MRR. The process results showed that maximum MRR achieved (2.40) mm³/min when machining feed rate (100) mm/min, spindle speed (1000) r.p.m, and depth of cut (0.6) mm while good surface roughness (0.41 µm) when machining feed rate (100) mm/min, spindle speed (1000) r.p.m, and depth of cut (0.2) mm. The level of importance of the machining parameters for material removal rate and surface roughness and is determined by using Taguchi designing experiments and the variance analysis (ANOVA).