Theoritical Prediction And Application Of Instantaneous Cutting Force For Solid End Milling Cutters

Milling operation is one of the most widely applied processes of machining metal, which has an important utilization in manufacturing aerospace and automobiles parts. Solid end mills are being widely used in machining parts sides, formed surfaces, slots, small planes, especially in the various cavities of die molds. Milling force is an vital physical output parameters in milling process. It is the key basis for the calculation of cutting power and milling torque, analysis of cutting heat, tool wear, tool life, machining precision of work-pieces and machined surface qualities. Milling force has an important significance for the design and application of machining tools as well as cutting tools, tool holders, optimizing the NC programs and proper selection of cutter geometry, cutting parameters.This dissertation presents a series of mathematical models for predicting instantaneous cutting force of cylindrical milling cutters, ball end milling cutters, corner radius end milling cutters and variable pitch-helix end milling cutters. In these models, the shearing effect and ploughing effect separately yet simultaneously are presented. The number and distribution of the elementary cutting edges involved in cutting action can be instantaneously determined by geometric analysis, which is efficiently, accurately and prone to programming. The proposed models are validated through milling experiments of TC11,45#steel and1Cr18Ni9Ti. The results show that there is a good agreement between the experimental results and the simulated ones.In the cutting system, reasonable tools geometry and cutting parameters have directly effects on product quality, costs, production cycle and the whole production system’s economic benefits. Numerical simulation method is proposed to study the impact law of cutter geometry and cutting parameters on the milling force. This research provides a theoretical basis for tool structure design and cutting parameter optimization.Based on the effect on machining results, a set of assessment criteria about instantaneous milling force is devloped. On the basis of the assessment criteria, new machining process for two kind of typical thin wall parts is obtained, which is a new attempt in themachining process optimization methods.A software system-’Cutting Force Predicting Software System for High Speed Milling V1.0’is developed based on commercially available mathematical software MATLAB. The callback functions are written by the M language. The friendly human-machine interface is implemented by using GUI tool. This software operates quickly and stably. It can be used to accurately predict the instantaneous milling force for cylindrical milling cutters, ball end milling cutters, corner radius end milling cutters with given tool geometries (such as cutter diameter, helix angle, number of teeth) under different cutting parameters (such as feed per tooth, axial and radial depth-of-cut). The output results of the software system include plotting milling force oscillograph traces and calculating the maximum, the minimum and average value of resultant force, feeding direction force component, the perpendicular to the feeding direction force component and axial direction force component. This software system takes full advantage of powerful numerical computation capability of computer machining. It uses simple application methods such as inputting or searching various parameters. The development of this software system provides great convenience for tool designer optimizing tool geometry and process engineer choosing cutting parameters by using cutting force mold.