Machining Strategy And Toolpath Generation Method For Pocket Flank Milling

Due to the non-uniform remaining materials at the corner,the cutting force suddenly increases in the flank milling process,which aggravates tool wear.The sharp change of the curvature of tool path leads to severe vibration of cutting tool and machining tool.The above problems seriously affect the machining quality of the workpiece.Associating with the National Science and Technology Key Project and requirements from aviation manufacturing industry,this paper studies on the complex relationship among the cutting force,the dynamic characteristics of machine tool and the toolpath of pocket flank milling and proposes a new machining strategy and toolpath generation method considering the constraints of the cutting force and the dynamic characteristics of machine tool to address the issue in the pocket flank milling process.The main ideas are as follow:(1)The relationship among the machining strategy of flank milling,the cutting force and the dynamic characteristics of machine tool is studied.The relationship between the cutting force and cutting parameters such as cutting engagement angle and feedrate,and the relationship among the dynamic characteristics of machine tool and curvature of tool path and feedrate are established according to the characteristics of flank milling,building up the basis of the generation of the toolpath and the feedrate planning of the flank milling process.(2)Considering the constraints of the cutting force and the dynamic characteristics of machine tool,a toolpath generation method of pocket flank milling is proposed.Based on corner-looping milling strategy,the cutting engagement angle is adjusted to ensure the stability of cutting force.The G2 continuity of tool path at the corner is realized using a pair of clothoid curve.The tool path can guarantee the stability of the process and suits for high-speed processing.(3)A feedrate planning method for the tool path in this paper is studied.The maximum feedrate is calculated according to the cutting force,the dynamic characteristics of the machine tool and the tool path curve.The advantage of the tool path of pocket flank milling in this paper is fully realized.And on the premise of guaranteeing the processing quality,the machining efficiency further improves.(4)The toolpath generation system of pocket flank milling is developed,which realizes automatic generation of tool path and plan of feedrate based on cutting force and machine dynamic characteristics.The experiment shows that,compared with the traditional method,the toolpath proposed in this paper can improve machining quality and efficiency.