Skip to content
Licensed Unlicensed Requires Authentication Published by Oldenbourg Wissenschaftsverlag October 1, 2020

The influence of the process parameters on the surface integrity during peripheral milling of Ti-6Al-4V

Der Einfluss der Prozessstellgrößen auf die Oberflächenintegrität beim Umfangsfräsen von Ti 6Al 4V
Matthias Wimmer, Muhammed Zubair Shahul Hameed, Christoph Wölfle, Vanessa Weisbrodt, Michael Friedrich Zaeh, Ewald Werner, Christian Krempaszky and Thomas Semm
From the journal tm - Technisches Messen


The titanium alloy Ti-6Al-4V represents a significant metal portion of state-of-the-art aircraft structural and engine components. When critical structural components in the aerospace industry are manufactured with the objective to reach high reliability levels, surface integrity is one of the most relevant parameters used for evaluating the quality of machined surfaces. The residual stresses and the surface alteration induced by machining titanium alloys are critical due to safety and sustainability issues. In this paper, a series of end milling experiments was conducted to comprehensively characterize the surface integrity at various milling conditions. The experimental results have shown that the surface roughness value increases with the feed and the cutting velocity. However, the residual stress state in the surface layer zone is influenced by the variation of the process control variables. Here, compressive residual stresses occur both in cutting and in feed direction. In addition, a new type of sensory tool holder is presented, which should enable the indirect measurement of residual stresses during the milling process.


Die Titanlegierung Ti-6Al-4V wird für die Herstellung von Flugzeugstruktur- und Triebwerkskomponenten verwendet. Wenn kritische Strukturkomponenten in der Luft- und Raumfahrtindustrie mit dem Ziel hergestellt werden, ein hohes Zuverlässigkeitsniveau zu erreichen, ist die Oberflächenintegrität einer der wichtigsten Parameter, die zur Bewertung der Qualität der endbearbeiteten Oberflächen verwendet wird. Die Eigenspannungs- und die Oberflächenveränderung, die durch die Bearbeitung von Titanlegierungen auftreten, sind aufgrund von Sicherheits- und Nachhaltigkeitsaspekten kritisch. In diesem Beitrag wurde eine Reihe von Umfangsfräsversuchen durchgeführt, um die Oberflächenintegrität bei verschiedenen Fräsbedingungen umfassend zu charakterisieren. Die experimentellen Ergebnisse haben gezeigt, dass die Oberflächenrauheitswerte durch Änderungen des Vorschubs pro Zahn und der Schnittgeschwindigkeit nicht signifikant beeinflusst werden. Der Eigenspannungszustand in der Randschichtzone ist jedoch durch die Variation der Prozessstellgrößen beeinflusst. Hierbei treten Druckeigenspannungen sowohl in Schnitt- als auch in Vorschubrichtung auf. Darüber hinaus wird ein neuartiger sensorischer Werkzeughalter vorgestellt, der die indirekte Messung von Eigenspannungen während des Fräsprozesses ermöglichen soll.

Funding source: Deutsche Forschungsgemeinschaft

Award Identifier / Grant number: SPP 2086

Funding statement: The scientific work has been supported by the DFG within the research priority program SPP 2086.


The authors thank the DFG for this funding and intensive technical support.


1. Z. C. Yang, D. H. Zhang, C. F. Yao, J. X. Ren, S. G. Du. Effects of high-speed milling parameters on surface integrity of TC4 titanium alloy. Journal of Northwestern Polytechnical University 27, 538–543, 2009.Search in Google Scholar

2. D. Ulutan, T. Ozel. Machining induced surface integrity in titanium and nickel alloy: A review. International Journal of Machine Tools & Manufacture 51, 250–280, 2011.10.1016/j.ijmachtools.2010.11.003Search in Google Scholar

3. D. Yang, X. Xiao, Y. Liu, J. Sun. Peripheral milling-induced residual stress and its effect on tensile–tensile fatigue life of aeronautic titanium alloy Ti–6Al–4V. The Aeronautical Journal 123, 212–229, 2019.10.1017/aer.2018.151Search in Google Scholar

4. C. H. Che-Haron, A. Jawaid, The effect of machining on surface integrity of titanium. Journal of Materials Processing Technology 166, 188–192, 2005.10.1016/j.jmatprotec.2004.08.012Search in Google Scholar

5. L. Chen, T. I. El-Wardany, W. C. Harris. Modeling the effects of flank wear land and chip formation on residual stresses. CIRP Annals – Manufacturing Technology 53, 95–98, 2004.10.1016/S0007-8506(07)60653-2Search in Google Scholar

6. Z. G. Wang, M. Rahman, Y. S. Wong. Tool wear characteristics of binderless CBN tools used in high-speed milling of titanium alloys. Wear 258, 752–758, 2005.10.1016/j.wear.2004.09.066Search in Google Scholar

7. B. Griffiths. Manufacturing surface technology. Surface integrity and functional performance. Penton Press, London, 2001.Search in Google Scholar

8. N. A. K. M. Amin, A. F. Ismail, N. M. K. Khairusshima. Effectiveness of uncoated WC–Co and PCD inserts in end milling of titanium alloy—Ti–6Al–4V. Journal of Materials Processing Technology 192/193, 147–158, 2007.10.1016/j.jmatprotec.2007.04.095Search in Google Scholar

9. P. Litwa, K. K. Wika, A. Zonuzi, C. Hitchens. The influence of cutting conditions on surface integrity in high feed milling of Ti-6Al-4V with supercritical CO2 cooling. MM Science Journal Special, 3071–3077, 2009.10.17973/MMSJ.2019_11_2019053Search in Google Scholar

10. M. Y. Wang, H. Y. Chang. Experimental study of surface roughness in slot end milling AL2014-T6. International Journal of Machine Tools and Manufacture 44, 151–157, 2004.10.1016/j.ijmachtools.2003.08.011Search in Google Scholar

11. J. I. Hughes, A. R. C. Sharman, K. Ridgway. The effect of tool edge preparation on tool life and workpiece surface integrity. Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 218, 1113–1123, 2004.10.1243/0954405041897086Search in Google Scholar

12. J. Sun, Y. B. Guo. A comprehensive experimental study on surface integrity by end milling Ti–6Al–4V. Journal of Materials Processing Technology 209, 4036–4042, 2009.10.1016/j.jmatprotec.2008.09.022Search in Google Scholar

13. L. N. Lopez de lacalle, J. I. Perez, J. Llorente, J. A. Sanchez. Advanced cutting conditions for the milling of aeronautical alloys. Journal of Materials Process Technology 100, 1–11, 2000.10.1016/S0924-0136(99)00372-6Search in Google Scholar

14. J. L. Canteroa, M. M. Tardiob, J. A. Cantelia, M. Marcosc, M. H. Miguelez. Dry drilling of alloy Ti–6Al–4V. International Journal Machine Tools Manufacturing 45, 1246–1255, 2005.10.1016/j.ijmachtools.2005.01.010Search in Google Scholar

15. J. Repper, M. Hofmann, C. Krempaszky et al. Effect of macroscopic relaxation on residual stress analysis by diffraction methods. Journal of Applied Physics 112, no. 6, 64906, 2012.10.1063/1.4752877Search in Google Scholar

16. P. J. Withers. Residual stress and its role in failure. Reports on Progress in Physics 70, no. 12, 2211–2264, 2007.10.1088/0034-4885/70/12/R04Search in Google Scholar

17. C. Krempaszky, E. A. Werner, M. Stockinger. Measurement of Marcoscopic Residual Stress and Resulting Distortion during Machining. Materials Science and Technology, 2005.Search in Google Scholar

18. B. Denkena, D. Nespor, V. Böß et al. Residual stresses formation after re-contouring of welded Ti-6Al-4V parts by means of 5-axis ball nose end milling. CIRP Journal of Manufacturing Science and Technology 7, no. 4, 347–360, 2014.10.1016/j.cirpj.2014.07.001Search in Google Scholar

19. E. K. Henriksen. Residual stresses in machined surfaces. Trans. ASME 73, 265–278, 1951.Search in Google Scholar

20. K. Okushima, Y. Kakino. A study on the residual stress produced by metal cutting. Memoirs of the Faculty of Engineering, Kuyoto 34, 234–248, 1972.10.1080/00207546308947828Search in Google Scholar

21. R. Pederson. Microstructure and phase transformation of Ti-6Al-4V. PhD Thesis, Luleå University of Technology, 2002.Search in Google Scholar

22. B. B. He. Two-dimensional x-ray diffraction. Wiley, Hoboken, NJ, 2009.10.1002/9780470502648Search in Google Scholar

23. M. G. Moore, W. P. Evans. Mathematical Correction for Stress in Removed Layers in X-Ray Diffraction Residual Stress Analysis. SAE International, Warrendale, PA, 1958.10.4271/580035Search in Google Scholar

24. Y. Altintas. Manufacturing automation. 2nd edition. Cambridge University Press, NY, USA, 2012.Search in Google Scholar

Received: 2020-07-20
Accepted: 2020-09-20
Published Online: 2020-10-01
Published in Print: 2020-11-26

© 2020 Walter de Gruyter GmbH, Berlin/Boston

Scroll Up Arrow