Sustainable Turning of the Ti-6Al-4V alloy at Low Feed Rates: Surface Quality Assessment

Titanium alloys are widely used in the aeronautic industry in which repair and maintenance operations are usually required. Because titanium is a difficult-to-machine material, it is recommended the use of cutting fluids to achieve good results. However, the cost and environmental impact of cutting fluids encourages the use of sustainable alternatives. The present study analyses the use of dry machining and cold-compressed air for turning Ti-6Al-4 V bars. Surface quality was analyzed evaluating the use of low feed rates and different types of tools and tool holders. As main conclusion, it can be affirmed that the feed rate is the most influential factor on the surface roughness (Ra and Rz). The surface roughness decreases at the higher feed rate until a certain machining time; afterwards, it increases with the increase of the feed rate.