Sensitivity analysis of cutting parameters considering cutting forces and surface roughness in High Speed Ball End milling process

Ball end milling cutter is a special type of end milling cutter which is frequently used for producing complex geometries and intricate shapes on variety of materials. Selection of the cutting parameters are very critical in order to achieve good surface finish, dimensional accuracy and lower cutting forces. Sensitivity analysis is the technique which is used to identify the critical cutting parameters and rank them according to their importance. In the present research a mathematical model for cutting forces and surface roughness in high speed ball end milling developed using rotary central composite design. The experiments were conducted using for parameters such as cutting speed (V), feed (f), axial (At) and radial (Ar) depth of cut. Analysis of variance (ANOVA) revealed a strong correlation exists between the predicted and experimental results as evidenced by the obtained the value of R2-adj (98.36%). At was the most influencing parameters accounting 47.12% followed by f and V. The developed models were used for sensitivity analysis based on the absolute method. The developed mathematical was checked for adequacy using the ANOVA. From the sensitivity analysis it was observed that radial (Fy) and axial (Fz) forces are highly sensitive to At whereas tangential cutting force (Fx) is most sensitive to the Ar. All the force components decreased with increasing V. Surface roughness is partially sensitive to cutting speed. For axial depth of cut 1.4 mm, Ra not influenced with the change in radial depth of cut and cutting speed.