Grinding of high performance materials with spherical mounted points

The 5-axis grinding with mounted points is a flexible manufacturing process, able to machine parts of complex geometries of ductile and brittle materials such as nickel-based alloys and high performance ceramics. By using 5 axes, two new process parameters are added in relation to the conventional grinding with cylindrical tools, the tilt and the lead angles. These angles, responsible for the tool axis orientation in relation to the workpiece normal, are plenty studied in 5-axis milling processes. However, its effects in grinding processes are not fully researched, leaving potential room for technological improvement. The current work aims at generating knowledge and increasing the efficiency of grinding of high performance materials with spherical mounted points for a quality, time and cost efficient manufacturing. The analytical description of the process is supported by a novel numerical model, developed to simulate the engagement area, grain indentation and to provide a prediction of the ground surface. Moreover, technological investigations were carried out to analyse the kinematics of grinding with spherical mounted points and its effects on Inconel 718 and hot isostatically pressed silicon nitride HIPSN. Finally, the findings were focused on 5-axis grinding of a HIPSN turbine impeller.