Milling Force Modeling And Experiment Research Based On The Fourier Series

NC milling tool is one of the most important basic equipment in machinery manufacturing industry. Its logical directions of development are high precision, high efficiency and low cost. The traditional NC milling documents are only edited from the perspective of geometry instead of the physical state during processing, so conservative milling conditions are adopted in order to ensure the safety. It restricts the tool's performance to full play and impacts the processing quality and efficiency. In this paper, a milling force model based on Fourier series is set up to describe the physical state of NC milling process. The milling force model is used for NC milling allowance optimization to set up an example for NC milling conditions optimization. The principal tasks are as follows:End milling and ball-end milling processes are analyzed using differential geometry. Micro-cutter force model is set up taking into account the shearing mechanism and the plowing mechanism. Contact area between workpiece and tool is measured through analytic geometry analysis and Z-map simulation. Then total milling force model is set up though integral within the region in contact. A milling force model in Fourier series form is established through Fourier transforming the periodically milling force.Linear equations for cutting coefficients of end milling and ball-end milling are made up through analysis of the zero-frequency items of milling force series when using slot milling experiments. Cutting experiments are done on a NC milling tool with a milling dynamometer, and cutting coefficients are regressed by the experimental data. Milling forces under certain milling conditions are modeled through numerical integration in MATLAB. The modeled milling forces and the measured forces are in good agreement. The proposed milling force model is verified.2.5-dimensional surface is dispersed in order to meet the machining accuracy condition using geometric analysis, and cutter-contact points are programmed. The cutter-location points are established by vector operations. The allowance point which can hold the milling force extent in horizontal plain to be constant is calculated through the cutter-contact point and the cutter-location point using milling force model, and milling allowance optimization are operated by calculating all the allowance points. Two numerical examples are operated to check milling allowance optimization.