Modeling and Structural Analysis of Tool Wear in Vertical Milling Centre

Abstract

The cutting forces exerted by the cutting tool on the work piece during a machining action to be identified in order to control the tool wear and occurrence of vibration, thus to improve tool-life. Modeling of cutting forces in milling is often needed in machining automation. The objective of this study is to predict the effects of cutting parameters on the variations of cutting forces during end milling operation of EN series steel alloy material. The EN 8, EN 44, EN 19 and EN 31 specimens have been machined on vertical milling machine. The cutting forces have been measured using the piezoelectric dynamometer for varying the feed rate, speed and depth of cut. The cutting forces evaluated were used as input for parametric analysis in Ansys 11.0.Software. The transient analysis has been done for a specified duration of time. The maximum stressed area and stress values were calculated using Ansys ls solver. Response surface methodology have been used by designing three factors and the five levels central composite rotatable design matrixes with full replication; for planning, conduction, execution and development of mathematical models. The coefficients of 2nd order quadratic equations were calculated using SYSTAT software. The average cutting forces have been determined at defined value of the parameters (feed, speed, depth of cut) in tangential, radial, and axial direction per tooth period. The immersion and axial depth of cut were maintained constant. A comparison between modeling and experiment also has been presented. This model and analysis are useful not only for predicting the tool wear but also for selecting optimum process parameters for achieving the stability of the end milling process.