Abstract
Accurate seam tracking plays a critical role in acquisition of good weld. During laser butt joint welding, the laser beam focus must be controlled to follow the weld trajectory. The key problem to be solved is the automatic identification of weld position. An approach to detect the micro gap weld (gap width is less than 0.05 mm) based on magneto-optical imaging (MOI) is proposed. The laser butt joint welding of carbon steel was carried out. A magnetic excitation device was used to magnetize the weldment, and it was found that magnetic field distribution at the weld was different from other regions. The magnetized weldment was detected by using a magneto-optical sensor, and magneto-optical images of the weld were captured. By analyzing and processing weld MO images with low contrast and strong magnetic field noises, the weld center position could be detected accurately. Weld MO images at different laser welding speeds were investigated to analyze the varieties of image characteristics. Experimental results indicated that the magneto-optical imaging technique could be applied to detect the micro gap weld accurately, which provides a novel approach for automatic identification and tracking of micro gap weld during laser welding.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Gao XD, You DY, Katayama S (2012) Infrared image recognition for seam tracking monitoring during fiber laser welding. Mechatronics 22(4):370–380
Shao Y, Wang ZZ, Zhang YM (2011) Monitoring of liquid droplets in laser-enhanced GMAW. Int J Adv Manuf Technol 57:203–214
Riahi M, Amini A (2013) Effect of different combinations of tailor-welded blank coupled with change in weld location on mechanical properties by laser welding. Int J Adv Manuf Technol 67:1937–1945
Hamidinejad SM, Hasanniya MH, Salari N, Valizadeh E (2013) CO2 laser welding of interstitial free galvanized steel sheets used in tailor welded blanks. Int J Adv Manuf Technol 64(1–4):195–206
Gao X, Mo L, Wen Q, Katayama S (2013) Neural network model for recognizing joint offset during fiber laser welding. Weld J 92(9):251–257
Steele J, Mnich C, Debrunner C, Vincent T, Liu S (2005) Development of closed-loop control of robotic welding process. Int J Adv Manuf Technol 32(4):350–355
Gao XD, Wen Q (2013) Monitoring of High-power fiber laser welding based on principal component analysis of molten pool configuration. Laser Phys 23:126001–126008
Huang W, Kovacevic R (2012) Development of a real-time laser-based machine vision system to monitor and control welding processes. Int J Adv Manuf Technol 63(1–4):235–248
Quintino L, Costa A, Miranda R, Yapp D, Kong CJ (2007) Welding with high power fiber lasers—a preliminary study. Mater Des 28(4):1231–1237
Xu D, Fang Z, Chen H (2012) Compact visual control system for aligning and tracking narrow butt seams with CO2 gas-shielded arc welding. Int J Adv Manuf Technol 62:1157–1167
Gao XD, You DY, Katayama S (2012) seam tracking monitoring based on adaptive Kalman filter embedded Elman neural network during high power fiber laser welding. IEEE Trans Ind Electron 59(11):4315–4325
Fitzpatrick GL, Thome DK, Skaugset RL, Shih EY, Shih WC (1993) Magneto-optic/eddy current imaging of aging aircraft: a new NDI technique. Mater Eval 51(12):1402–1407
Fitzpatrick GL, Thome DK, Skaugset RL, Shih WC (1996) Magneto-optic/Eddy current imaging of subsurface corrosion and fatigue cracks in aging aircraft. Rev Prog Quant Nondestruct Eval 15:1159–1166
Zeng Z, Liu X, Deng Y, Udpa L, Xuan L, Shih WC, Fitzpatrick GL (2006) A parametric study of magneto-optic imaging using finite-element analysis applied to aircraft rivet site inspection. IEEE Trans Magn 42(11):3737–3744
Park U, Udpa L, Stockman GC (2004) Motion-based filtering of magneto-optic imagers. Image Vision Comput 22(3):243–249
Udpa L, Shih WCL, Fitzpatrick GF (2001) Improved magneto-optic sensors for detection of subsurface cracks and corrosion in aging aircraft, in Proc. 5th Joint NASA/FAA/DoD Conf. Aging Aircraft, Orlando, FL, Sep 10–13
Deng Y, Zeng Z, Tamburrino A (2007) Automatic classification of magneto-optic image data for aircraft rivet inspection. Int J Appl Electromagn Mech 25:375–382
Cheng YH, Zhou ZF (2006) Application of the magneto-optic Faraday effect in NDT. INSIGHT 48(5):290–293
Radtke U, Zielke R, Rademacher HG, Crostack HA, Hergt R (2001) Application of magneto-optical method for real-time visualization of eddy currents with high spatial resolution for nondestructive testing. Opt Lasers Eng 36(3):251–268
Liu GQ, Le ZQ, Shen DF (2001) Magnetooptics. Shanghai Science and Technology Press, Shanghai, pp 43–45
Cheng Y, Jiang S, Luo G (2010) Visual detection of sub-surface defects using enhanced eddy current microscope. COMPEL 29(2):347–354
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Gao, X., Chen, Y. Detection of micro gap weld using magneto-optical imaging during laser welding. Int J Adv Manuf Technol 73, 23–33 (2014). https://doi.org/10.1007/s00170-014-5811-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00170-014-5811-x