The effect of laser power on the machinability of the Ti-6Cr-5Mo-5V-4Al beta titanium alloy during laser assisted machining

Laser assisted machining has been a field of extensive research during the past decade as it is a promising solution to enhance the machinability of many difficult-to-cut materials including titanium alloys. The fundamental principle of the technology is the application of a laser heat source to soften the workpiece material ahead of the cutting tool. Previous literature published on the laser assisted machining of several alpha and alpha/beta titanium alloys (mainly CP Ti and Ti-6Al-4V) reported significant reduction in cutting forces. However, a recent study carried out by the authors on the beta titanium alloy (Ti-6Cr-5Mo-5V-4Al) reported a beneficial reduction in cutting forces between cutting speeds of 25-100 m/min with a laser power of 1200 W. This is due to the fact that beta titanium alloys are specifically designed to exhibit high temperature strength and fracture toughness. In this paper, further research was carried out to assess the effect of laser power on the possibility of broadening the cutting speed range beyond 100 m/min when machining Ti-6Cr-5Mo-5V-4Al. The effect of the laser beam on the cutting forces and cutting temperature has been reported. It was found that increasing the laser power from 1200 W to 1600 W resulted in an extension of the beneficial cutting speed range to 125 m/min