Optimization of Machining Parameters for Titanium Alloy (Grade-5) Using CBN Tool Insert with Different Nose Radius Using Taguchi Technique

Abstract

In this research paper, focus is on the machinability study of titanium (grade-5) alloy using the CBN cutting tool inserts having nose radius of 0.4 mm and 0.8 mm. Taguchi method provides a simple, systematic and efficient methodology for optimization of the cutting parameters. Taguchi design of experiment approach has been used for planning the experiments and analysis of experimental data obtained. An orthogonal array L₂₇ (3¹³), the signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) are employed to investigate the cutting characteristics of titanium alloy (grade-5). Four cutting parameters namely cutting speed, feed rate, depth of cut and approach angle each at three levels are optimized with considerations of surface roughness and cutting force as machinability criteria. Through this study, not only can the optimal cutting parameters for turning operations be obtained but also the main cutting parameters that affect the cutting performance in turning operations can be found. From the results, it is observed that the approach angle and feed rate have considerable influence on the machinability of titanium alloys. Surface roughness increased with increasing feed rate but decreased with increasing cutting speed and depth of cut. The predicted results are fairly close to experimental values and hence the results can be used for prediction satisfactorily. Experimental results are provided to confirm the effectiveness of this approach.

Keywords: Machinability, Taguchi, turning, roughness