Simulation of low rigidity part machining applied to thin-walled structures

Abstract

OATAO is an open access repository that collects the work of Toulouse researchers and makes it freely available over the web where possible.Simulation of low rigidity part machining applied to thin-walled structuresAbstract The aim of this study is to evaluate the modelling of machining vibrations of thin-walled aluminium workpieces at high productivity rate. The use of numerical simulation is generally aimed at giving optimal cutting conditions for the precision and the surface finish needed. The proposed modelling includes all the ingredients needed for real productive machining of thin-walled parts. It has been tested with a specially designed machining test with high cutting engagement and taking into account all the phenomena involved in the dynamics of cutting. The system has been modelled using several simulation techniques. On the one hand, the milling process was modelled using a dynamic mechanistic model, with time domain simulation. On the other hand, the dynamic parameters of the system were obtained step by step by finite element analysis; thus the variation due to metal removal and the cutting edge position has been accurately taken into account. The results of the simulations were compared to those of the experiments; the discussion is based on the analysis of the cutting forces, the amplitude and the frequency of the vibrations evaluating the presence of chatter. The specific difficulties to perfect simulation of thin-walled workpiece chatter have been finely analysed.

Dynamics of thin-walled element milling expressed by recurrence analysis

“…The proposed model is validated and the theoretical findings show very good agreement with the experimental results [1]. Although, experimental results are very often compared with FEM results [3,17], the problem of experimental signal analysis remains an open question. Different methods of signal analysis are applied in order to recognize chatter vibrations in cutting operations, including multifractal and wavelet approaches [38], multiscale entropy [23] HilbertHuang transform [20], recurrence analysis [22], flicker-noise spectroscopy [21] and audio signal analysis [32].…”

“…Their predictions agree well with the experimental observations. Arnaud et al [3] presents the problem of modelling of machining vibrations of thin-walled aluminium workpieces at high productivity rate. These authors employ numerical simulations, FEM analysis and experimental tests in order to determine optimal cutting conditions.…”

A synthetical stability method for cutting parameter optimization to assure surface location accuracy in flexible part milling

“…2 and isolated from other high structure modes, which adopted here is to simplify the complexity of the real system as possible. Not alike the real flexible part in industry which has multiple modes and different mode shape, such as thin-wall workpiece, blades and impellers, the different mode shapes of part structure make the frequency response function varying with cutting path [5,6,[18][19][20][21]. However, the method presented here can be easily extended to consider the multiple-mode cases.…”

The Milling Process Monitoring Using 3D Envelope Method

“…Correlation between the output signals (cutting forces, vibration) and the type of features which appeared on the workpiece surface were investigated by use of time and frequency analysis of the output signals [11]. An envelope method to milling process characterization is taken into account.…”