Cutting parameters influence on surface integrity of dry-turned Ti6Al4V alloy

Surface integrity is a high-interest characteristic of machined parts in the aeronautical industry. Numerous variables are related to the surface integrity and require to be studied as a whole. Generally, the cutting parameters affect these variables' results, especially in sustainable machining operations. This work analyses the cutting speed and feed influence on different parameters such as the roughness, macrogeometrical deviations and microhardness of Ti6Al4 V turned in dry. All variables have been taken into account simultaneously, given the synergy between the different input and output variables. In general terms, feed seems to be the most influential variable in macrogeometrical and microgeometrical deviations, while cutting speed affects mainly the microhardness parameter. In addition, an optimisation process has been carried out. In the first step, the optimal cutting parameters were obtained for the lowest cutting speed and the lowest feed values due to the roughness is the predominant variable. Therefore, a second optimisation step was performed excluding this variable, optimising the macrogeometrical deviations and the microhardness. In this case, higher cutting speed and feed values seem to be the optimal cutting parameters. Finally, different decision maps were plotted to facilitate the cutting parameter selection according to the property to optimise.