The new technology of welding with impacting rotation is put forward to decrease the wave-like deformation of the TC4 thin plate weldment. The thermal stress and strain are vital to understand the mechanism of control...The new technology of welding with impacting rotation is put forward to decrease the wave-like deformation of the TC4 thin plate weldment. The thermal stress and strain are vital to understand the mechanism of controlling the wave-like deformation. In order to know the development of internal thermal stress and strain, finite element method is utilized for- the stress and strain are difficult to be investigated by experimental methods during the welding process. Temperature field, thermal stress evolution and distortion of thin plate are compared with the test results such as weld thermal cycle, residual stress sectioning measurement, and the deflection of the thin plate respectively. By the finite element analysis and test results verification, the meehaaism of the technology to control the wave-like deformation is brought forward, non-uniform thermal elastic strain between compressive plastic region and elastic extensive region is diminished by a certain amount of extensive plastic deformation by welding with impacting rotation process.展开更多
T-joint titanium alloy structures are commonly used in aircraft manufacturing,and their laser welding process is relatively mature,but due to the strict requirements of the airplane production,the angular deformation ...T-joint titanium alloy structures are commonly used in aircraft manufacturing,and their laser welding process is relatively mature,but due to the strict requirements of the airplane production,the angular deformation caused by uneven heat input across the sheet is still not negligible,so active control needs to be imposed.In this paper,an active deformation control method based on programmable multi-point flexible support is proposed and validated.In response to the problem that the traditional rigid clamping and pre-stressing are not adapted to the T-structure thin sheet,this study has designed a multi-point flexible support with microcontroller and electric actuators,which can monitor the stress state of the current support position in real time during the welding process and make dynamic adjustment,so that the weld deformation could be effectively reduced in this way.展开更多
The paper describes the simulation of impact loads applied on plate panels with welding-induced residual stresses and deformation (WSD). Numerical simulations using FEM are carried out to study the influence of weldin...The paper describes the simulation of impact loads applied on plate panels with welding-induced residual stresses and deformation (WSD). Numerical simulations using FEM are carried out to study the influence of welding-induced residual stresses and deformation on the impact strength of plate panels. Welding is simulated using a three dimensional thermal mechanical coupled finite element method. The welding stress and deformation are taken as the initial imperfections in the impact strength analysis and their influence on the behavior of plate panels subjected to impact loadings. The impact loadings from the three directions, the lateral direction and two in-plane directions of the plate panels are studied. Results show a certain reduction in the impact strength due to the existence of welding stress and deformation in the plate panels. It is found that the reduction of impact force is strongly influenced by the welding deformation and the impact directions in the plate panels. This reduction is more significant when the impact force is in the lateral direction.展开更多
The residual deformation in thin-plate butt weldments without wire filling was investigated by simulative and experimental methods.The good consistency on the residual deformation between the simulation result and tes...The residual deformation in thin-plate butt weldments without wire filling was investigated by simulative and experimental methods.The good consistency on the residual deformation between the simulation result and test measurement data indicates that the contact mode can be used to simulate the butt welding process of thin plates without wire filling.The longitudinal residual tensile stress in the weld zone lead to the buckling deformation of thin-plate weldments,and the appearance of buckling deformation would in turn reduce the peak value of longitudinal residual tensile stress.As for the thin-plate butt weldments,the tensile stresses in the weld and its neighboring zone are produced in the post-weld cooling process and have not peak until the temperature of the welds dropped to near room temperature.展开更多
文摘The new technology of welding with impacting rotation is put forward to decrease the wave-like deformation of the TC4 thin plate weldment. The thermal stress and strain are vital to understand the mechanism of controlling the wave-like deformation. In order to know the development of internal thermal stress and strain, finite element method is utilized for- the stress and strain are difficult to be investigated by experimental methods during the welding process. Temperature field, thermal stress evolution and distortion of thin plate are compared with the test results such as weld thermal cycle, residual stress sectioning measurement, and the deflection of the thin plate respectively. By the finite element analysis and test results verification, the meehaaism of the technology to control the wave-like deformation is brought forward, non-uniform thermal elastic strain between compressive plastic region and elastic extensive region is diminished by a certain amount of extensive plastic deformation by welding with impacting rotation process.
基金supported by the National Natural Science Foundation of China(Grant No.52275304 and 51975014).
文摘T-joint titanium alloy structures are commonly used in aircraft manufacturing,and their laser welding process is relatively mature,but due to the strict requirements of the airplane production,the angular deformation caused by uneven heat input across the sheet is still not negligible,so active control needs to be imposed.In this paper,an active deformation control method based on programmable multi-point flexible support is proposed and validated.In response to the problem that the traditional rigid clamping and pre-stressing are not adapted to the T-structure thin sheet,this study has designed a multi-point flexible support with microcontroller and electric actuators,which can monitor the stress state of the current support position in real time during the welding process and make dynamic adjustment,so that the weld deformation could be effectively reduced in this way.
文摘The paper describes the simulation of impact loads applied on plate panels with welding-induced residual stresses and deformation (WSD). Numerical simulations using FEM are carried out to study the influence of welding-induced residual stresses and deformation on the impact strength of plate panels. Welding is simulated using a three dimensional thermal mechanical coupled finite element method. The welding stress and deformation are taken as the initial imperfections in the impact strength analysis and their influence on the behavior of plate panels subjected to impact loadings. The impact loadings from the three directions, the lateral direction and two in-plane directions of the plate panels are studied. Results show a certain reduction in the impact strength due to the existence of welding stress and deformation in the plate panels. It is found that the reduction of impact force is strongly influenced by the welding deformation and the impact directions in the plate panels. This reduction is more significant when the impact force is in the lateral direction.
基金This work was supported by the Stable Supporting Fund of Science and Technology on Reactor Fuel and Materials Laboratory(JCKYS2019201073)the Guangdong Innovative and Entrepreneurial Research Team Program(2016ZT06G025).
文摘The residual deformation in thin-plate butt weldments without wire filling was investigated by simulative and experimental methods.The good consistency on the residual deformation between the simulation result and test measurement data indicates that the contact mode can be used to simulate the butt welding process of thin plates without wire filling.The longitudinal residual tensile stress in the weld zone lead to the buckling deformation of thin-plate weldments,and the appearance of buckling deformation would in turn reduce the peak value of longitudinal residual tensile stress.As for the thin-plate butt weldments,the tensile stresses in the weld and its neighboring zone are produced in the post-weld cooling process and have not peak until the temperature of the welds dropped to near room temperature.
