Research On Cutting Force Modeling Of Five - Axis NC Machining Of Circular Milling Cutter

After the financial crisis, the US government proposed a ‘return of manufacturing’ strategy. This reflects the importance of manufacturing to a country. China is a big manufacturing country, but it is not strong. On March 25, 2015, The Prime Minister Li Keqiang convened and presided over the executive meeting of the state council about accelerating the implement of the ‘Made in China 2025’ strategy. The high-end CNC machines have become one of the ten key areas that will be developed. Both the national medium-and long-term program for scientific and technological development(2006-2020) and the National Natural Science Fund Committee report about mechanical engineering development strategy, mechanical and manufacturing science(2006-2020), included the design, manufacturing and measurement of complex surfaces and the other key technologies in the field that will be focused on in the manufacturing industry. 5-axis NC machine is the representative of high-end NC machine and special for processing complex surfaces. Nowadays more and more enterprises equipped with 5-axis NC machine, but lack relevant theories, long-term experience of using 5-axis NC machine and the database of cutting parameters to guide the choosing for cutting parameters not to mention the optimization. Because of this, enterprises cannot make full use of the advanced equipment and at the same time, the incorrect process parameters may result in poor surface quality, tool wear and so on. The cutting force is the main factor that must be consideration in choosing the cutting parameters and has a great influence on the tool life,stability and surface quality in machining. But the studies on cutting force of 5-axis NC machining are almost all about ball-end mill. The researches about other tools are required as development of precision and speed in modern manufacturing.Therefore, this paper is about the model of cutting force of ring mill in 5-axis NC machining. Before the modeling of cutting force, the geometric modeling in 5-axis NC machining is first required. The objective of geometric modeling is to determine the boundary of the tool workpiece engagement surfaces. But with the continuous change of tool axis vector, the tool workpiece engagement surfaces also change. So they are very difficult to calculate.In this paper, the workpiece surface is expressed with NURBS surface, and the expression of torus of the ring mill during processing is derived. The tool workpiece engagement surfaces are calculated through the surface and surface intersection algorithm. The problem of calculating the tool workpiece engagement surfaces is transformed into the problem of surface/surface intersection. Next, the model of cutting force in 5-axis NC machining is established and the simulation algorithm is written. Finally we make a simulation to the cutting force in the machining of free surface with a ring mill.