Statistical analysis of process parameters during machining of Titanium alloy (Ti-6Al-4V) on shaper machine

Abstract

Productivity of titanium alloys is high dependent on the cutting speeds and usually higher cutting speeds (above 100m/min) results in greater productivity. Tool life and the energy consumption during this cutting process is related to cutting speeds. This research is mainly focused on machining titanium alloys (Ti-6Al-4V) on a shaper machine using PVD coated carbide inserts (CNMG 120408NN). The reason for selecting shaper machine instead of conventional milling was the cutting forces that are comparatively higher than the conventional milling process. Parameters selected as machining variables are cutting speed (40 ~ 100m/min) and depth of cut (0.2mm, 0.3mm and 0.4mm). Feed rate is not involved in this machining process as whole length of 100mm is subjected to one cut at a time. The process is performed on titanium alloys (Ti-6Al-4V) in dry conditions. Surface roughness of the sample, chip formation and flank wear growth of the tool has been investigated under different cutting speeds and depths of cuts. The tool life was found to be shorter at high cutting speeds because of abrasive wear resistance and accumulation of heat on the tool chip interface. Surface roughness is reduced at higher cutting speeds but not that much because of tool wear, hence surface roughness is decreasing with a slight negative slope. This means better surface finish The depth of cut had very little effect on the performance parameters. Increasing depth of cut increase the surface roughness. The results help in the selection of Optimum cutting conditions that will minimize the tool wear and improve surface finish. These optimum conditions also help in lowering the specific cutting energy for machining titanium alloys (Ti-6Al-4V).