[1] Ishide T, Shono S, Ohmae T, et al. Fundamental study of laser plasma reduction method in high power CO2 laser weld-ing[C]//Proceedings of the International Conference on Laser Materials Processing-Science and Application, Osaka, Japan, 1987: 187-191.

[2] Arata Y, Abe N, Oda T. Fundamental phenomena in high power CO2 laser welding[J]. Transactions of JWRI, 1985, 14(1): 5-11.

[3] Beck M, Berger P, Hugel H. The effect of plasma formation on beam focusing in deep penetration welding with CO2 Lasers[J]. Journal of Physics D: Applied Physics, 1995, 28(12): 2430-2442.

[4] Wang C M, Meng X X, Huang W, et al. Role of side assisting gas on plasma and energy transmission during CO2 laser welding[J]. Journal of Materials Processing Technology, 2011, 211(4): 668-674.

[5] Tse H C, Man H C, Yue T M. Effect of magnetic field on plasma control during CO2 laser welding[J]. Optics & Laser Technology, 1999, 31(5): 363-368.

[6] Peng Yun, Chen Wuzhu, Wang Cheng, et al. Controlling the plasma of deep penetration laser welding to increase power efficiency[J]. Journal of Physics D: Applied Physics, 2001, 34(21): 3145-3149.

[7] Arata Y, Abe N, Oda T. Fundamental phenomena in high power CO2 laser (Report II): vacuum laser welding[J]. Transactions of JWRI, 1985, 14(2): 217-222.

[8] Katayama S, Kobayashi Y, Mizutani M, et al. Effect of vacuum on penetration and defects in laser welding[J]. Journal of Laser Applications, 2001, 13(5): 187-192.

[9] Katayama S, Abe Y, Mizutani M, et al. Deep penetration welding with high-power laser under vacuum[J]. Transactions of JWRI, 2011, 40(1): 15-19.

[10] Katayama S, Youhei A, Mizutani M, et al. Development of deep penetration welding technology with high brightness laser under vacuum[J]. Physics Prodedia, 2011, 12: 75-80.

[11] B rner C, Dilger K, Rominger V, et al. Influence of ambient pressure on spattering and weld seam quality in laser beam welding with the solid-state laser[C]//Proceedings of the 30th International Congress on Applications of Lasers & Elec-tro-Optics, Orlando, FL, USA, 2011: 621-629.

[12] Cai C, Peng G C, Li L Q, et al. comparative Study on Laser Welding Characteristics of Aluminium Alloy under Atmospheric and Subatmospheric Pressures[J]. Science and Technology of Welding and Joining, 2014, 19(7): 547-553.

[13] 彭根琛. 铝与镍合金的真空环境激光焊接特性研究[D]. 哈尔滨: 哈尔滨工业大学, 2015: 28-44.

    Peng Genchen. Laser welding characteristics of aluminum and nickel-base alloys under vacuum environment[D]. Harbin: Harbin Institute of Technology, 2015: 28-44.

[14] 罗燕. 负压激光焊接过程蒸气羽烟及熔池行为研究[D]. 上海: 上海交通大学, 2015: 32-33.

    Luo Yan. Research on plasma plume and molten pool behavior in fiber laser welding under subatmospheric pressure[D]. Shanghai: Shanghai Jiao Tong University, 2015: 32-33.

[15] Chen Qintao, Tang Xinhua, Lu Fenggui, et al. Study on the effect of laser-induced plasma plume on penetration in fiber laser welding under subatmospheric pressure[J]. The Interna-tional Journal of Advanced Manufacturing Technology, 2015, 78(1-4): 331-339.

[16] Luo Yan, Tang Xinhua, Lu Fenggui, et al. Experimental study on deep penetrated laser welding under local subatmospheric pressure[J].The International Journal of Advanced Manufac-turing Technology, 2014, 73(5-8): 699-706.

[17] 罗燕, 唐新华, 芦凤桂, 等. 局部负压激光焊缝成形特点及其影响因素[J]. 中国激光, 2014, 41(6): 0603008.

    Luo Yan, Tang Xinhua, Lu Fenggui, et al. Effects of welding parameters on bead formation of laser welding under subat-mospheric pressures[J]. Chinese Journal of Lasers, 2014, 41(6): 0603008.

[18] Yang S, Wang J, Carlson B E, et al. Vacuum-assisted laser welding of zinc-coated steels in a gap-free lap joint configura-tion[J]. Welding Journal, 2013, 92(7): 197-s-204-s.

[19] 包海涛, 刘金合, 刘锟, 等. 真空激光焊接工艺参数对AZ31镁合金熔深的影响及缺陷分析[J]. 应用激光, 2008, 28(5): 366-370.

    Bao Haitao, Liu Jinhe, Liu Kun, et al. Effect of vacuum laser welding parameter on AZ31 magnesium alloy penetration and flaw analysing[J]. Applied Laser, 2008, 28(5): 366-370.

[20] 包海涛, 刘金合, 刘锟, 等. 低功率YAG激光真空焊接工艺[J]. 航空制造技术, 2008(23): 92-95.

    Bao Haitao, Liu Jinhe, Liu Kun, et al. Low-power YAG laser welding process under vacuum condition[J]. Aeronautical Manufacturing Technology, 2008(23): 92-95.

[21] Youhei A, Yousuke K, Hiroshi N, et al. Effect of reduced pressure atmosphere on weld geometry in partial penetration laser welding of stainless steel and aluminium alloy with high power and high brightness laser[J]. Science and Technology of Welding and Joining, 2014,19(4): 324-332.

[22] Verwaerde A, Fabbro R, Deshors G. Experimental study of continuous CO2 laser welding at subatmospheric pressures[J]. Journal of Applied Physics, 1995, 78(5): 2981-2984.

[23] 姜梦. 真空环境下激光焊接等离子体特性研究[D]. 哈尔滨: 哈尔工业大学, 2015: 37-48.

    Jiang Meng. Study on the characteristics of plasma in laser welding under vacuum conditions[D]. Harbin: Harbin Institute of Technology, 2015: 37-48.

[24] 姜梦, 陶汪, 陈彦宾, 等. 真空激光焊接焊缝成形及等离子体特征[J]. 中国激光, 2016, 43(4): 0403010.

    Jiang Meng, Tao Wang, Chen Yanbin, et al. Characteristics of bead formation and plasma plume in fiber laser welding under vacuum[J]. Chinese Journal of Lasers, 2016, 43(4): 0403010.

[25] Luo Yan, Tang Xinhua, Lu Fenggui, et al. Spatial distribution characteristics of plasma plume on attenuation of laser radia-tion under subatmospheric pressure[J]. Applied Optics, 2015, 54(5): 1090-1096.

[26] Pang Shengyong, Hirano K, Fabbro R, et al. Explanation of penetration depth variation during laser welding under variable ambient pressure[J]. Journal of Laser Applications, 2015, 27(2): 022007.

[27] Pang Shengyong, Chen Xin, Zhou Jianxin, et al. 3D transient multiphase model for keyhole, vapor plume, and weld pool dynamics in laser welding including the ambient pressure ef-fect[J]. Optics and Lasers in Engineering, 2015, 74: 47-58.

[28] Fabbro R, Hirano K, Pang Shengyong. Analysis of the physical processes occurring during deep penetration laser welding under reduced pressure[J]. Journal of Laser Applications, 2016, 28(2): 022427.

[29] B rner C, Krüssel T, Dilger K. Process characteristics of laser beam welding at reduced ambient pressure[C]//Proceeding of the SPIE Volume 8603, High-Power Laser Materials Pro-cessing: Lasers, Beam Delivery, Diagnostics, and Applications II, San Francisco, CA, US, 2013: 86030M.

[30] Reisgen U, Olschok S, Jakobs S, et al. Welding with the laser beam in vacuum[J]. Laser Technik Journal, 2015, 12(2): 42-46.