6Huntington C A, Engar T W. Laser welding of aluminum and aluminum alloys [ J ]. Welding Journal, 1983 ( 4 ) : 105 - 107.
7Fujinaga S,Takenaka H,Narikiyo T,et al. Direct observa- tion of keyhole behavior during pulse modulated high - pow- er Nd: YAG laser irradiation[ J ]. Journal of Physics D: Ap- plied Physics, 2000,33 (5) :492 - 497.
8Seto N, Katayama S, Matsunawa A. High - speed simultan ous observation of plasma and keyhole behavior during hij power CO2 laser welding:Effect of shielding gas on porosi formation [ J ]. Journal of Laser Applications, 2000,12 ( 6 245 - 250.
9Tang Z, Seefeld T, Vollertsen F. Grain Refinement by Las / Welding of AA 5083 with Addition of Ti/B [ J ]. Physi / Procedia,2011,12 : 123 - 133.
10Pourkia N, Emamy M, Farhangi H, et al. The effect of Ti and Zr elements and cooling rate on the microstructure and ten- sile properties of a new developed super high - strength alu- minum alloy [ J ]. Material Science and Engineering: A, 2010,527 (20) :5318 - 5325.