Cutting Force Modeling Of Five-axis NC Machining By Fillet-end Milling Cutter

With the rapid development of modern science and technology,the machining precision and surface roughness of complex curved surface parts are higher in the aviation,automobile,medical and other industries.The tool position of five-axis CNC machining tools can follow the flexible changes of the machined surface,and the processing benefits Excellent,so the five-axis machine tool has great advantages in the processing of complex curved surfaces in high-end technology manufacturing.The cutting force directly affects the machining quality and processing efficiency of the machined parts during the five-axis machining process,while the undeformed chip thickness and the cutting force coefficient have a great influence on the cutting force,which is an important factor that can not be ignored in accurately establishing the cutting force model.At present,most of the research is on the cutting force of the machining process of the three-axis CNC machine tool and the cutting force model of the ball-end milling cutter.Because the actual blade path of the five-axis machining is more complicated,the research on the five-axis machining of the annular milling cutter is less.This paper mainly studies the undeformed chip thickness modeling,cutting force coefficient identification and cutting force prediction in five-axis NC machining with ring milling cutter.The main research work of the thesis is as follows:(1)For the problem of the direction and size of the cutting force caused by the rake angle and the side yaw angle of the five axes,according to the geometry of the cutting edge of the ring milling cutter,the three-dimensional cycloidal model of the actual movement trajectory of the cutter teeth during the five-axis machining milling process is established;Geometric modeling was performed in the global coordinate system.(2)Based on the three-dimensional cycloidal model of the actual movement of the cutter teeth,a pair of cutting thickness control points formed by the adjacent cutter teeth on the front and rear surfaces of the tool workpiece contact area are described,and the undeformed chip thickness model at different positions of thecutting edge is established.The influence of the inclination angle,the side angle and the feed amount per tooth on the thickness of the undeformed chip;the equation of the true blade path under the deformation of the tool is derived,the model of the undeformed chip thickness under the tool deformation is established,and the tool deformation is analyzed for the undeformed chip.The law of influence of thickness.(3)Two methods are used to identify the cutting force coefficient.One is based on the average cutting force method to solve the cutting force coefficient,and the other is based on the mechanical model of the cutting force coefficient identification method,through a single horizontal cutting experiment.The cutting force coefficient curve is obtained,and finally the least-squares method is fitted to obtain the instantaneous machining cutting force coefficient.(4)An accurate model of cutting force in five-axis machining process was established,which was verified by simulation and experiment using MATLAB software.