Study on developing predicted system model of cutting-edge trajectory for micro-milling process based on tool runout error, chip thickness and force signal

The cutting-edge trajectory of micro end mills directly affects machining stability, surface quality and tool wear involved in micro milling process. However, the size effect and geometric characteristics of micro end mills make its cutting-edge trace diverge markedly from the traditional milling cutter paths. The cutting-edge trajectory prediction system model is specifically developed for a two-edged micro end mill in high-speed rotation consisting of input layer, model layer and output layer in this study. The input layer comprises the static and dynamic tool runout parameters through measurement and calculation, and the micro-milling force model considering the undeformed cutting thickness and tool runout offset. The model layer encompasses micro milling material removal model and tool path model that account for tool runout and cutting thickness. Finally, the tool path, slot width, micro-milling forces and surface roughness can be obtained from the output layer. Besides, the influence laws of runout parameters on the micro-milling force, surface roughness, and slot width of micro-milled polycarbonate were revealed. The developed cutting-edge trajectory predicted system model is very useful for optimizing tool conditions, compensating machining errors and reducing residual burrs on workpieces.