“…4, the AE detection system included AE R6ɑ sensor, 2/4/6 preamplifier and AE win TM software in the robotic milling process. It is well known that acoustic emission is defined as a physical phenomenon in which instantaneous elastic waves are generated within the material due to the rapid release of energy [26]. In the cutting process, the major sources for AE waves include the shear deformation of workpiece in the first deformation zone (shear zone), the plastic deformation of workpiece and the sliding friction between tool and chip in the second deformation zone (chip-tool interface), extrusion and friction between flank face and newly formed surface of workpiece in the third deformation zone (tool flank-workpiece interface), the plastic deformation and breakage in the chip, collisions between chip and tool, tool vibration, and chipping and fracture of the tool [26][27][28], as the details shown in Fig.…”