Effect of Cooling on Bending Angle and Microstructure in Laser Tube Bending with Circumferential Scanning


1 Department of Mechanical Engineering, University of Birjand, Birjand, Iran

2 Faculty of Mechanical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran



Laser tube bending is a flexible forming process. Two irradiation methods of axial and circumferential scanning are generally used to form metal tubes. The two most important disadvantages of circumferential scanning are its lower bending angle and the time interval required between each scan for cooling purpose. In this research, a novel cooling strategy during laser tube bending with circumferential scanning is proposed to eliminate these disadvantages. The effects of this method on the bending angle and total production time are experimentally investigated. Also, the changes in the microstructure of the tube after bending are studied. The bending angle obtained at each scan using this strategy was increased more than 1.5 times with much less production time and energy consumption. Besides, the undesired effect of HAZ was significantly reduced. It is shown that this new cooling technique can highly improve the efficiency of laser tube bending by the circumferential scanning method.


[1]  S. Silve, W. Steen, B. Podschier, Laser forming tubes: a discussion of principles, International Congress on Applications of Lasers & Electro-Optics 1 (1998) 151-160.

[2] J. Kraus, Basic process in laser bending of extrusion using the upsetting mechanism, Laser Assisted Net Shape Engineering 2, Proceedings of the LANE (1997) 431-438.

[3]  W. Li, Y. L. Yao, Laser Bending of tubes: mechanism, analysis, and prediction, Journal of Manufacturing Science and Engineering 123 (2001) 674-681.

[4]  J. Zhang, P. Cheng, W. Zhang, M. Graham, J. Jones, M.  Jones, Y.L. Yao, Effects of scanning schemes on laser tube bending, Journal of Manufacturing Science and Engineering 128 (2006) 20-33.

[5]  S. Safdar, L. Li, M. A. Sheikh, Finite element simulation of laser tube bending: Effect of scanning schemes on bending angle, distortions and stress distribution, Optics and Laser Technology 39 (2007) 1101-1110.

[6]  X. Y. Wang, Y. H. Luo, J. Wang, W. J. Xu, D. M. Guo, Scanning path planning for laser bending of straight tube into coil-shape tube, International Journal of Advanced Manufacturing Technology 69 (2013) 909-917.

[7]  G. Sheikholeslami, J. Griffiths, S. P. Edwardson, K. Watkins, G. Dearden, Laser forming of ERW steel square tubes within metallurgical constraints, Key Engineering Materials 549 (2013) 68-75.

[8]  Y. He, L. Heng, Z. Zhiyong, Z. Mei, L. Jing, L. Guangjun, Advances and trends on tube bending forming technologies, Chinese Journal of Aeronautics 25 (2012) 1-12.

[9]  M. S. CheJamil, E. R. ImamFauzi, C. S. Juinn, M. A. Sheikh, Laser bending of pre-stressed thin-walled nickel micro-tubes, Optics and Laser Technology 73 (2015) 105-117.

[10]    K. I. Imhan, B. T. H. T. Baharudin, A. Zakaria, M. I. S. B. Ismail, N. M. H. Alsabti, A. K. Ahmad, Investigation of material specifications changes during laser tube bending and its influence on the modification and optimization of analytical modeling, Optics and Laser Technology 95 (2017) 151-156.

[11]    K.I. Imhan, B. T. H. T. Baharudin, A. Zakaria, M. I. S. B. Ismail, N. M. H. Alsabti, A. K. Ahmad, Features of laser tube bending processing based on laser forming: a review, Journal of Lasers, Optics & Photonics 5 (2018) 1-8.

[12]    K. I. Imhan, B. T. H. T. Baharudin, A. Zakaria, M.I.S.B. Ismail, N.M.H. Alsabti, A.K. Ahmad, Improve the material absorption of light and enhance the laser tube bending process utilizing laser softening heat treatment, Optics and Laser Technology 99 (2018) 15-18.

[13]    F. Li, S. Liu, A. Shi, Q. Chu, Q. Shi, Y. Li, Research on laser thread form bending of stainless steel tube, International Journal of Precision Engineering and Manufacturing 20 (2019) 893-903.

[14]    S. M. H. Seyedkashi, M. Hoseinpour Gollo, J. Biao, Y.H. Moon, Laser bendability of SUS430/ C11000/ SUS430 laminated composite and its constituent layers, Metals and Materials International 22 (2016) 527-534.

[15]    J. Cheng, Y. L. Yao, Microstructure integrated modeling of multiscan laser forming, Journal of Manufacturing Science and Engineering 124 (2002) 379-388.

[16]  H. D. Abazari, S. M. H. Seyedkashi, M. Hoseinpour Gollo, Y. H. Moon, Evolution of microstructure and mechanical properties of SUS430/C11000/SUS430 composites during the laser-forming process, Metals and Materials International 23 (2017) 865-876.