Consideration of key process parameters for achieving robust and uniform cutting of Ti-6Al-4V sheet metal using fiber laser with nitrogen assisted gas


  • Varit Poshyananda Faculty of Engineering, Chulalongkorn University
  • Jidsucha Darayen Faculty of Engineering, Chulalongkorn University
  • Krittima Tumkhanon Faculty of Engineering, Chulalongkorn University
  • Chedtha Puncreobutr Faculty of Engineering, Chulalongkorn University
  • Atchara Khamkongkaeo Faculty of Engineering, Chulalongkorn University
  • Boonrat Lohwongwatana Faculty of Engineering, Chulalongkorn University


Titanium, Ti-6Al-4V, Laser Cuttinge, Recast Layer, Heat-Affected Zon


In laser cutting, to work on sensitive and intricate materials, such as titanium, requires rigorous control of parameters to achieve the best cutting results due to high power throughput and rapid cutting speed. Titanium is known for severe reaction with oxygen and nitrogen at elevated temperatures, however the more inert argon assist gas is cost prohibitive in commercial application. To achieve cut quality using nitrogen as an assist gas in titanium cutting, careful control is needed to prevent the formation of hard and brittle martensite as well as nitride- and oxide- phases. To better understand the roles of industrial grade raw materials and assist gas in commercial laser cutting, phase transformation, heat affected zone (HAZ) cut quality and the relationships amongst parameters have been selected to mimic industrial setups. 2mm thick titanium sheet was cut by a fiber laser cutting process using nitrogen assist gas by varying three cutting parameters including (i) laser power (1000-3000 watts), (ii) cutting speed (4000-26000 mm/min), and (iii) assist gas pressure (1-20 bars). Cut quality assessment was interpreted through the scanning electron microscope (SEM) and optical observation to link with mechanical properties from bending and v-notch fracture tests. The results showed that increase in cutting speed will limit the thickness of heat-affected zone (HAZ) which varied from 20-500 um. Pressure of the assist gas should be above a threshold value of 8 bar to assure complete ejection of the liquid melt pool. Key observations were reported along with root causes, such as, (i) non-uniformed and thick HAZ layer, (ii) thick and brittle recast (RC) layer, as well as (iii) micro-tearing due to localized expansion of nitrogen rich phase.


Download data is not yet available.


D. P. Shidid, M. H. Gollo, M. Brandt, and M. Mahdavian, “Study of effect of process parameters on titanium sheet metal bending using Nd: YAG laser,” Optics & Laser Technology, vol. 47, pp. 242-247, 2013.

N. Andersson and C. Granberg, “Laser cutting in Ti-6Al-4V sheet: DOE and evaluation of process parameters Informative,” Master Degree Thesis, Department of Materials and Manufacturing Technology, Chalmers University of Technology: Gothenburg, Sweden, 2015.

J. Sieniawski, W. Ziaja, K. Kubiak, and M. Motyka, J. Sieniawski and W. Ziaja, eds. “Microstructure and mechanical properties of high strength two-phase titanium alloys,” in Titanium Alloys - Advances in Properties Control, London: IntechOpen Limited, 2013, pp. 69-80.

F. Torrent, L. Lavisse, P. Berger, J. M. Jouvard, H. Andrzejewski, G. Pillon, S. Bourgeois, and M. C. Marco de Lucas, “Wavelength influence on nitrogen insertion into titanium by nanosecond pulsed laser irradiation in air,” Applied Surface Science, vol. 278, pp. 245-249, 2013.

B. Yilbas, S. Akhtar, and O. Keles, “Laser straight cutting of Ti-6Al-4V alloy: Temperature and stress fields,” in Materials and Surface Engineering, J. P. Davim, ed. Woodhead Publishing Reviews: Mechanical Engineering Series, UK: Woodhead Publishing, 2012, pp. 243-265.

I. A. Almeida, W. de Rossi, M. S. F. Lima, J. R. Berretta, G. E. C. Nogueira, N. U. Wetter, and N. D. Vieira, “Optimization of titanium cutting by factorial analysis of the pulsed Nd:YAG laser parameters,” Journal of Materials Processing Technology, vol. 179, pp. 105-110, 2006.

J. D. Majumdar, “Laser Gas Alloying of Ti- 6Al-4V,” Physics Procedia, vol. 12, pp. 472- 477, 2011.

Y. Yin, L. Hang, S. Zhang, and X. L. Bui, “Thermal oxidation properties of titanium nitride and titanium–aluminum nitride materials - A perspective for high temperature air-stable solar selective absorber applications,” Thin Solid Films, vol. 515, pp. 2829-2832, 2007.

F. H. Pollard and P. Woodward, “The stability and chemical reactivity of titanium nitride and titanium carbide,” Transactions of the Faraday Society, vol. 46, pp. 190-199, 1950.

D. P. Satko, J. B. Shaffer, J. S. Tiley, S. L. Semiatin, A. L. Pilchak, S. R. Kalidindi, Y. Kosaka, M. G. Glavicic, and A. A. Salem, “Effect of microstructure on oxygen rich layer evolution and its impact on fatigue life during high-temperature application of α/β titanium,” Acta Materialia, vol. 107, pp. 377- 389, 2016.

T. Zhang, Z. Wu, R. Hu, F. Zhang, H. Kou, and J. Li, “Influence of nitrogen on the microstructure and solidification behavior of high Nb containing TiAl alloys,” Materials & Design, vol. 103, pp. 100-105, 2016.

L. D. Scintilla, L. Tricarico, A. Wetzig, and E. Beyer, “Investigation on disk and CO2 laser beam fusion cutting differences based on power balance equation,” International Journal of Machine Tools and Manufacture, vol. 69, pp. 30-37, 2013.

O. O. Kardas, O. Keles, S. Akhtar, and B. S. Yilbas, “Laser cutting of rectangular geometry in 2024 aluminum alloy: Thermal stress analysis,” Optics & Laser Technology, vol. 64, pp. 247-256, 2014.

O. S. Bursi, M. D'Incau, G. Zanon, S. Raso, and P. Scardi, “Laser and mechanical cutting effects on the cut-edge properties of steel S355N,” Journal of Constructional Steel Research, vol. 133, pp. 181-191, 2017.

C. H. Fu and Y. B. Guo, “Laser cutting simulation of nitinol stent alloy with moving heat flux,” presented at The International Conference on Shape Memory and Superelastic Technologies American Society for Metals, Pacific Grove, CA, May 12-16, 2014.

L. Shanjin and W. Yang, “An investigation of pulsed laser cutting of titanium alloy sheet,” Optics and Lasers in Engineering, vol. 44, pp. 1067-1077, 2006.

A. Kumar Pandey and A. Kumar Dubey, “Simultaneous optimization of multiple quality characteristics in laser cutting of titanium alloy sheet,” Optics & Laser Technology, vol. 44, pp. 1858-1865, 2012.

H. Ozaki, M. Q. Le, H. Kawakami, J. Suzuki, Y. Uemura, Y. Doi, M. Mizutani, and Y. Kawahito, “Real-time observation of laser cutting fronts by X-ray transmission,” Journal of Materials Processing Technology, vol. 237, pp. 181-187, 2016.

H. G. Salem, M. S. Mansour, Y. Badr, and W. A. Abbas, “CW Nd:YAG laser cutting of ultra low carbon steel thin sheets using O2 assist gas,” Journal of Materials Processing Technology, vol. 196, pp. 64-72, 2008.




How to Cite

V. . Poshyananda, J. Darayen, K. Tumkhanon, C. . Puncreobutr, A. . Khamkongkaeo, and B. Lohwongwatana, “Consideration of key process parameters for achieving robust and uniform cutting of Ti-6Al-4V sheet metal using fiber laser with nitrogen assisted gas”, J Met Mater Miner, vol. 28, no. 2, Jan. 2019.



Original Research Articles

Most read articles by the same author(s)