The Influence of the Metalworking Fluid on Tool Wear in Milling Inconel 718

The understanding of tool wear mechanisms is fundamental to developing more productive machining processes. Therefore, the influence of different metalworking fluids on tool wear is studied when milling Inconel 718 using a rotating dynamometer, a stationary dynamometer, and a 3D microscope. A newly developed force model allows the interpretation of more than the maximal cutting force and explains the relation between tribological conditions, tool wear and process forces. In a novel setup, the coolant type was changed in the middle of the tool life to differentiate the direct influence of the coolant on the process forces and the indirect effect via tool wear. By fitting the model to the data, it is found that the metalworking fluid and the process parameters not only influence the wear rate globally, but also lead to different wear mechanisms. The 3D data of worn cutting edges confirms the existence of different wear mechanisms.