[1] [1] Xu Bin. Analysis and research of laser welding technology[J]. Technology Innovation and Application, 2013, (3): 41.

[2] [2] Genyu Chen, Mingjun Zhang, Zhi Zhao, et al.. Measurements of laser-induced plasma temperature field in deep penetration laser welding[J]. Optics & Laser Technology, 2013, (45): 551-557.

[3] [3] Zhang Jian, Yang Rui. Control of laser power during titanium alloy thin plate welding[J]. Chinese J Lasers, 2012, 39(1): 0103003.

[4] [4] Zhang Jian, Yang Rui. Weld penetration depth prediction of pulsed laser welding titanium alloy thin plate[J]. Chinese J Lasers, 2012, 39(3): 0303001.

[5] [5] Zhang Yi, Duan Linyong, Zhou Dianwu, et al.. Monitoring mechanism of plasma generated by laser welding galvanized steel with powder feeding[J]. Chinese J Lasers, 2012, 39(5): 0503005.

[6] [6] Liu Jinglei, Chen Yanbin, Xu Qinghong. The correlation of acoustic signal and penetration laser welding[J]. Transactions of the China Welding Institution, 2006, 27(1): 72-80.

[7] [7] Jiang Ping, Chen Wuzhu, Guo Jing, et al.. The FFT analyse of the acoustic signal on plasma in laser welding[J]. Laser Journal, 2001, 22(5): 62-63.

[8] [8] Wang Chunming, Hu Lunji, Hu Xiyuan, et al.. Plasma optical signal detection and analysis in the process of titanium alloy laser welding[J]. Transactions of the China Welding Institution, 2004, 25(11): 83-90.

[9] [9] Wang Chunming, Wu Songping, Hu Lunji, et al.. Identification of different laser welding penetration states based on multi-sensor fusion[J]. Chinses J Lasers, 2007, 34(4): 538-544.

[10] [10] Cherring B E. The use of electrostatic probes for plasma diagnostics-a review[J]. Plasma Process, 1982, 2(2): 113-139.

[11] [11] Bi Chao, Yang Lijun, Xu Wenhao. An electrical detection of the fluctuating plasma of laser welding with a passive probe[J]. Journal of Physics D: Applied Physics, 2012, 45(38): 385202.

[12] [12] Liu Tong, Yang Lijun, Wang Lijun, et al.. A comparative analysis of the pas-sive electric probe detection and spectrum diagnosis of laser-induced plasma[J]. Spectroscopy and Spectral Analysis, 2014, 34(2): 289-292.

[13] [13] Y Kawahito, N Matsumoto, M Mizutani, et al.. Characterisation of plasma induced during high power fibre laser welding of stainless steel[J]. Science and Technology of Welding and Joining, 2008, 13(8): 744-748.

[14] [14] Jun Wang, Chunming Wang, Xuanxuan Meng, et al.. Study on the periodic oscillation of plasma vapor induced during high power fibre laser penetration welding[J]. Optics & Laser Technology, 2012, 44(1): 67-70.