Dynamic Characteristics in Cutting Processses for Precision Machining
The accuracy and surface roughness of a machined component is strongly dominated by the dynamic characteristics of the machine tool while the most important factor related to precision machining is the dynamic behaviors during cutting processes. The main objective of this study is to develop a thermo-elastic-plastic coupling dynamic cutting model under large deformation for precision machining and so that the model can be used to predict several variations of cutting mechanics variables. The flow stress in the model is considered as a function of strain, strain rate and temperature and the critical value of the strain energy density of the workpiece is utilized as a chip separation criterion. A powerful FEM software is adopted to create a complete numerical solution for this model. During the analysis, the cutting tool is incrementally advanced forward in a step-by-step manner, from an incipient stage of tool-workpiece engagement to a steady state of chip formation. Three different dynamic cutting processes are introduced in this study, i.e., wave cutting, wave removing and wave on wave cutting. Various levels of frequencies, of amplitudes and of phase angle associated with different kinds of sinusoidal surface waviness are arranged during each simulation case. A whole simulation of dynamic cutting process is undertaken and the fluctuations of the dynamic cutting force during each dynamic cutting process are determined.
Guo Fan JIN, Wing Bun LEE, Chi Fai CHEUNG and Suet TO
S. Y. Lin and Y.C. Fang, "Dynamic Characteristics in Cutting Processses for Precision Machining", Key Engineering Materials, Vols. 364-366, pp. 265-271, 2008