Comparison of novel TiN coated and uncoated carbide tool in CNC dry turning of EN31 to analyse chip profile

Abstract

The objective of the present study is to compare novel TiN coated and uncoated carbide tool during CNC turning of EN31 alloy steel to analyse chip profile. Materials and Methods: Two groups of cutting tool novel TiN coated and uncoated, are used for machining of EN31 in dry turning operation. The three input parameters selected for present experimental study are cutting speed (m/min), feed (mm/rev) and depth of cut (mm). Each parameter is varied at 3 different levels with the conduct of L9 experimental studies. The chip profile of EN31 is measured at 25 mm machined length. Two groups of experimental study are selected (novel TiN coated and uncoated) with 27 samples per group and chip thickness is measured on three chips taken from one experimental run and the average is utilized for chip thickness calculation. On the whole 54 samples are collected and measured for 2 groups. The sample size is calculated with 80 % of total pretest G power. Results: The chip thickness was found to be 16 % high when the machining process was done with coated tools when compared to uncoated tools. The value of the thickness of the chip(microns) was found to be low when a lower feed rate is given and value of thickness was high when we gave a higher feed rate. All the results obtained were analysed for its significance by SPSS software and the graphs were plotted and the level of significance was found to be 0.049 (p < 0.05). Conclusion: Within the limitations of this study, it was found that machining of selected material, EN31, by using novel TiN coated carbide tool results in maximum chip formation when compared with an uncoated carbide tool during wet turning process.