Dynamic Modeling And Stability Analysis For Milling System

Because of the discontinuity in milling processing, vibration happens periodically andripples leave on the part surface. The thickness of chip changes and chatter happens.Especially when stiffness of workpiece is relatively weak, chatter happens easier. Toresearch the stability of machining process has great significance to improve theprocessing technology, machining efficiency and quality. In this paper, mechanism andstability of milling process is deep researched. The two-dimensional dynamical model andmathematical model of milling that considering the dynamic characteristic of both tooland workpiece are built. The stability boundary graph is obtained through solving themathematical model. At last, some experiments are taken to verify the theory. And someimportant conclusions are gained. The concrete research contents are as follows:1. The dynamical model of milling process is built. The dynamical model of millingprocess that considering the dynamic characteristic of both tool and workpiece is builtbased on the conventional model. Mechanical force in milling process is analyzed andcutting-force model is built.2. The cutting force coefficients are demarcated through experiments using differentcutting parameters according to the cutting-force model. The cutting forces simulatedwith the cutting force coefficients are compared with the measured forces to verify theveracity.3. The stable boundary condition is derived according to the milling model. The modelparameters of tool system and workpiece system are got through hammering test.Then stable lobe graph is drawn and the result is verified through milling experiments.4. The effect of dynamic characteristics to the shape of lobe graph are analyzed bysimulation.Researches of this paper have guiding significance for milling with high efficiency under stable condition.