Research On Developing Fiber Laser Flexible Welding Equipment And Welding Process Of TA15 Titanium Alloy

Aerospace industry, an important part of National Defense Science and Technology, has become a significant symbol of China’s strong comprehensive national strength with the improvement of its position. During the stage of the aerospace products’ machining, the welding technology becomes one of the main application technologies in the field of the aerospace industry with good reliability. Some new welding technologies represented by laser welding are widely used in aerospace industry for their superior performance.The flexible welding equipment based on fiber laser technology and robot system integration technology is simple, efficient and reliable, and it is widely used in aerospace industry. In this paper, a new type of fiber laser flexible welding equipment was designed, and the laser welding process of TA15 titanium alloy was studied by using the equipment. The work of the research includes:(1) The welding process of the TA15 titanium alloy is analysed in systematic approach.The lectron beam welding and laser welding, two different welding methods are compared, including the advantages and disadvantages of them. The feasibility of the deep penetration laser welding to weld TA15 titanium alloy is demonstrated. The key matters in the process of welding are introduced.(2) According to the use of new fiber laser flexible welding equipment and the hardware unit compatibility issues, the hardwares are selected and the technical scheme is designed. The hardware equipments include fiber laser, precitec welding joint, dust-cleaning fan, pneumatic unit, 6-axis robot and some other auxiliary units. After completing the equipment hardware assembly, a series of improvements are made in the layout of the optical fiber, the visualization of the operation process, the prevention of laser radiation and other details. Manuals about equipment operation and fault alarm solutions, and so on, are written. The safety training is carried out for operating personnel.(3) The electrical system integration scheme of the equipment is designed based on the national standard of electric industry and aerospace industry standard. DI/DO dot signals are defined for the WorkVisual software mated with the robot. The functions of the HMI and relatednotes of the robot programming are introduced in detail.(4) The influence of welding speed and welding power on welding joint quality is deeply studied using the orthogonal experimental method. The weld appearance, X-ray detection and tensile strength testing of welding quality results are analyzed. The optimization design is conducted to obtain two groups of welding process parameters for mass production.