Numerical Simulation of Machining Operations on Flexible Parts

Abstract:

Airspace industry components frequently need high added value part including some featuredifficult to manufacture. One of the best example is the thin walls of parts (airplanes frames orthe turbine blades) that have a very low stiffness. The finishing operations for high height to thicknessratio parts lead to chatter vibrations, unacceptable dimensional errors or poor surface finish. The optimalmachining strategy determination is often based on trial and error and may not be cost effective(acceptable conditions can be far from the optimum). Simulation of the milling process is a powerfulmean to accelerate the search for better cutting parameters. Cutting forces, vibrations, geometricerrors or roughness can be predicted before the production of the first parts. The classical mechanisticapproach is even though limited while machining flexible parts because the dynamic response ofthe workpiece changes with the position of the cutter. The objective of this paper is to demonstratethe adaptation of numerical simulation of milling operation for the machining of thin-walled plates.Three complementary approaches are developed: location-dependent stability lobes, quasi static approachand full dynamic simulation. Location dependent stability lobes extend the classical theoryto take into account the variation of dynamic response along the workpiece. Quasi static approach isintended to deal with form error during chatter-free machining operations. Full dynamic simulation isa more complex approach intended to simulate the behavior of the complete tool/machine/workpiecesystem. The numerical approach is compared to experimental tests performed on thin plate of titaniumalloys.

• Periodical: Key Engineering Materials (Volumes 554-557)
• Pages: 1984-1991
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.554-557.1984
• Online since: June 2013
• Authors: Edouard Rivière-Lorphèvre, Enrico Filippi, Pierre Dehombreux
• Keywords: Chatter Vibration, Form Error, Machining, Milling

References

[1] S. N. Grigoriev, A.A. Kutin, and V.V. Pirogov. Advanced method of nc programming for 5-axis machining. In Proceedings of the 5th CIRP Conference on High Performance Cutting, 2012.

DOI: 10.1016/j.procir.2012.04.016

[2] Y. Altintas and E. Budak. Analytical prediction of stability lobes in milling. Annals of the CIRP, 44:357--362, 1995.

DOI: 10.1016/s0007-8506(07)62342-7

[3] T. Insperger, B.P. Mann, G. Stepan, and P.V. Bayly. Stability of up-milling and down-milling, part 1: Alternative analytical methods. Int. J. Mach. Tools Manuf., 43:25--34, 2003.

DOI: 10.1016/s0890-6955(02)00159-1

[4] Y. Altintas, G. Stepan, D. Merdol, and Z. Dombovari. Chatter stability of milling in frequency and discrete time domain. CIRP Journal of Manufacturing Science and Technology, 1:35--44, 2008.

DOI: 10.1016/j.cirpj.2008.06.003

[5] O.C. Zienkiewicz. The finite element method 3rd edition ,. Mc Graw Hill, 1977.

[6] P. V. Bayly, B. P. Mann, T. L. Schmitz, D. A. Peters G. Stepan, and T. Inspeger. Effects of radial immersion and cutting direction on chatter instability in end-milling. In Proceeding of IMECE202 - ASME International Mechanical engineering Congress & Exposition, 2002.

DOI: 10.1115/imece2002-39116

[7] S. Seguy. De l'adaptation á la variation continue de la vitese de broche afin de controler le broutement en fraisage de parois minces: modĺisation et t́ude expérimentales. PhD thesis, Institut national polytechnique de Toulouse, 2008.

DOI: 10.1051/meca:2005048

[8] G. Peigne and Al. A model of milled surface generation for time domain simulation of high-speed cutting. Proc. Instn Mech. Engrs Part B: J Engineering Manufacture, 217 Number 7:919--930, July 2003.

DOI: 10.1243/09544050360686798

[9] M. L. Campomanes and Y. Altintas. An improved time domain simulation for dynamic milling at small radial immersion. Trans. ASME, 125:416--422, Augustus 2003.

DOI: 10.1115/1.1580852

[10] F. Ducobu, E. Riviére-Lorphévre, and E. Filippi. Dynamic simulation of the micro-milling process including minimum chip thickness and size effect. In Proceedings of ESAFORM 2012, pages 1269--1274, 2012.

DOI: 10.4028/www.scientific.net/kem.504-506.1269

[11] S. Engin and Y. Altintas. Mechanics and dynamics of general milling cutters. part I: Helical end mills. Int. J. Mach. Tools Manuf., 41:2195--2212, 2001.

DOI: 10.1016/s0890-6955(01)00045-1

[12] Y. Altintas, M. Eynian, and H. Onozuka. Identification of dynamic cutting force coefficients and chatter stability with process damping. CIRP Annals - Manufacturing Technology, 57:371--374, 2008.

DOI: 10.1016/j.cirp.2008.03.048

[13] Sebastien Seguy, Gilles Dessein, and Lionel Arnaud. Surface roughness variation of thin wall milling, related to modal interactions. Int. J. Mach. Tools Manuf., 48:261--274, 2008.

DOI: 10.1016/j.ijmachtools.2007.09.005

[14] Y Altintas. Manufacturing automation, Metal cutting, Machine tool vibration and CNC design. Cambridge university press, 2000.