USE OF DESIRABILITY FUNCTION APPROACH FOR OPTIMIZATION OF MULTIPLE PERFORMANCE CHARACTERISTICS OF THE SURFACE ROUGHNESS PARAMETERS IN CNC TURNING

This paper presents a desirability function approach in order to find out an optimal combination of machining parameters for multiple performance characteristics of the surface roughness parameters in CNC turning operation on mild steel. In the present study, experiments have been conducted using depth of cut, spindle speed and feed rate as cutting parameters for evaluating the roughness parameters such as centre line average (Ra), root mean square (Rq) and mean line peak spacing (Rsm). An orthogonal array (L9) is generated using the Taguchi design to carry out the experiments on AISI 1040 mild steel bar. The individual desirability values of each roughness parameters have been calculated and accumulate to calculate the overall desirability of the surface roughness in turning operation. The signal-to-noise ratio is employed to investigate the optimal combination of cutting parameters to yield maximum overall desirability. After the optimal level of cutting parameters has been find out, verification test is to be carried out to control the accuracy of analysis of results taken from the experiment.