A mathematical model of the cutting process in end milling is presented. A simple algorithm for processing the end milling force signals to detect chatter vibration is described. The model predicts variations of the cutting forces according for a range of cutting conditions, cutter geometrys, the relationship between the cutting forces and the chip load including relative positions of cutter to workpiece. In order to verify the force model, a series of experiments have been carried out. The model can predict the cutting forces, self-excited vibration, cutter deflection and surface roughness.
The cutting forces are presented and validated through experimental measurement for the avoidance of chatter. It has been shown that the methods are directly related to the spindle speed radial depth of cut and workpiece material. The basic principle of these techniques is to present the effects of the cutting parameters on the dynamic of the cutting forces and join these effects to the appearance of the chatter marks on the machined surface.
The proposed models have been proven to be useful on the cutting process and tool monitoring in end milling operations. Since the machined surface spoiled by chatter marks under the chatter conditions, the factors influenced the machined surface in CNC milling operations might be considered. A series of statistically planned experiments using design of experiment (DoE) have to be available for developing mathematical response model.
The model simulated using a standard mathematical package. It is simple, capable of simulating multi teeth cutters and can be easily expanded to accommodate any tool configuration and characteristics. The possible application of the model is to detect and eliminate chatter in milling. |
