Analysis Of Welding Residual Stress And Mechanical Properties Of Titanium Alloy Tube Plate Structure

In the international background of Aeronautics and Astronautics,each country pay more and more attention to aerospace Aerospace technology is not only a symbol of the nation science and technology level,but also shows great significance to the construction of national defense.As widely used material in aerospace field,the connection process of Tc4 titanium alloy has great influence on the structural strength and service life of spacecraft.Welding residual stress is an unavoidable problem of welding important manufacturing welding processes.Therefore,the research on the generation and elimination of residual stresses is attracting more and more attention.In this paper,an finite element software ANSYS is used to simulate the welding process and post-welding process of TC4 titanium alloy tube plate structure.Based on the basic principle of welding mechanics,a tube plate welding model is established.The distribution and variation of temperature field in welding process under heat source moving state are calculated by using double ellipsoid heat source model and life death unit technology.The results of the stress field are obtained by using the result of the temperature field as the loading condition by the sequential coupling method.The feasibility of the algorithm is verified by comparison with the combined reference and experimental results.In the post welding process,the two conditions of deep cold aging and ultrasonic shock are simulated,and the residual stress distribution in post welding process is obtained.The residual stress along a specific path is analyzed and compared.The results show that both the deep cold treatment and the ultrasonic treatment can effectively reduce the residual stress of the welding,and the peak value of the residual stress in the weld center is reduced.The ultrasonic impact can also improve the distribution of stress while reducing the peak of residual stress,and further enhance the strength and service life of components.However,the impact damage to members under impact is still to be considered.