Welding properties and molten pool flow behavior of TC4 titanium alloy by oscillating galvanometer laser

被引：0
作者：
Chen B. [1 ,2 ]
Meng Z. [1 ]
Ma C. [1 ]
Xi X. [1 ]
Wang X. [3 ]
Tan C. [1 ,2 ]
Song X. [1 ,2 ]
机构：
[1] Shandong Provincial Key Laboratory of Special Welding Technology, Harbin Institute of Technology, Weihai
[2] State Key Laboratory of Advanced Welding and Connection, Harbin Institute of Technology, Harbin
[3] Department of Mechanical Engineering, University College London, London
来源：
Hangkong Xuebao/Acta Aeronautica et Astronautica Sinica | 2022年 / 43卷 / 04期
关键词：
Grain refinement; Laser welding; Mechanical property; Molten pool flow; Oscillating laser welding; Titanium alloy;
D O I：
10.7527/S1000-6893.2021.25223
中图分类号：
学科分类号：
摘要：
Titanium alloys are widely used in aircraft and aerospace engines. Laser welding is an excellent welding method for joining titanium alloys, and the main problem currently existing is the degradation of joint performance due to porosity. Oscillating laser can significantly improve the keyhole behavior and molten pool flow state, thereby reducing porosity and refining grains, and eventually improving the joint properties in laser welding. Fiber laser was used to join the 4 mm thick TC4 titanium alloy using oscillating laser welding, and the weld formation, mechanical properties, grain refinement, molten pool flow and keyhole behavior before and after oscillating by 0.4 mm steps from 0.4 mm to 1.6 mm oscillating amplitude were compared and analyzed. The results show that keyhole-induced pores were significantly suppressed at a laser power of 4 kW, welding speed of 1.2 m/min, off-focus amount of 0, oscillating frequency of 100 Hz and oscillating amplitude of 0.8 mm, and the joint obtained can achieve the highest tensile strength of 1 025.03 MPa, which is 96% of that of the base material. Compared to the beam without laser oscillating, the upper grains of the joint with an oscillating amplitude of 0.8 mm were refined by 65%. The presence of circular laser oscillating caused the molten pool to be more stable, and gave directionality to the molten pool flow while the oscillating laser enlarged and stabilized the keyhole, reducing spatter and porosity. © 2022, Beihang University Aerospace Knowledge Press. All right reserved.
引用
收藏
相关论文
共 32 条
[1]  
LU K., Materials science. The future of metals, Science, 328, 5976, pp. 319-320, (2010)
[2]  
LIU S F, SONG X, XUE T, Et al., Application and development of titanium alloy and titanium matrix composites in aerospace field, Journal of Aeronautical Materials, 40, 3, pp. 77-94, (2020)
[3]  
SUN J G, GAO F Y, GAO Q, Et al., Study on microstructure and properties of hot-wire-TIG welded joint of TC4 titanium alloy, Development and Application of Materials, 34, 2, pp. 9-13, (2019)
[4]  
ZHAO W L, LIU X G, XIE P Y, Et al., Study on shear fatigue performance of TC4 titanium alloy diffusion bonded joints, Aeroengine, 46, 3, pp. 99-102, (2020)
[5]  
WANG S Q, XING B, ZHAO Q Z, Et al., Effect of heat treatment on microstructure and tensile properties of electron beam welded TC4/Ti60 joint, Electric Welding Machine, 50, 5, pp. 16-20, (2020)
[6]  
DU Z B, WANG W L, XIONG R., Study on the weld shape and performance control of vacuum electron beam welding of TC18 titanium alloy thin-walled shell, Welded Pipe and Tube, 43, 10, pp. 29-34, (2020)
[7]  
SHAO S, HUANG Y D, CHEN Y H., Research status on tools of friction stir welding in titanium alloy, Journal of Netshape Forming Engineering, 11, 5, pp. 115-122, (2019)
[8]  
LU Y, TURNER R, BROOKS J, Et al., Microstructural characteristics and computational investigation on electron beam welded Ti-6Al-4V alloy, Journal of Materials Processing Technology, 288, (2021)
[9]  
Puchkov P U., LI Y J, WANG J, Application and development of advanced welding technology by high-energy density beam, Aeronautical Manufacturing Technology, 54, 8, pp. 38-41, (2011)
[10]  
PENG N X., Study on Fresnel absorption in the keyhole during deep penetration laser welding of aluminum alloy 6016, (2018)
1234