Welding is commonly employed to connect large-scale components in practical engineering.Predicting the resulting deforma-tion and residual stresses during the welding process is typically essential.The thermal-elastic...Welding is commonly employed to connect large-scale components in practical engineering.Predicting the resulting deforma-tion and residual stresses during the welding process is typically essential.The thermal-elastic-plastic method simulates the welding process by examining heat distribution and elastic-plastic stresses.Despite its high computational accuracy,this method is often time-consuming,rendering it less suitable for large component welding predictions.In contrast,the inherent strain method skips the welding process and fo-cuses on the inherent strain in the weld and joint areas post-welding.This method is fast and convenient,particularly suitable for the analysis of large and complex structures.The results show that the error rate is 4.6%when using the inherent strain method to calculate the welding deformation of the test plate.In the calculation of welded parts,the error rate is 5%,which is within the tolerance of the actual engineering.In this paper,the simulation accuracy of the deformation results of the inherent strain method is validated by simulating fusion vacuum ves-sel mockup,aiming to reduce the cost of welding analysis by using this method and to provide reference for practical welding applications.展开更多
Through a modified inherent strain model based on the minimum residual stress and deformation,three building schemes with different building postures and support structures were evaluated by finite element analysis.Re...Through a modified inherent strain model based on the minimum residual stress and deformation,three building schemes with different building postures and support structures were evaluated by finite element analysis.Results demonstrate that according to the principle of reducing the overall height of the building and reducing the support structure with a large tilt angle from the building direction,the residual stress and deformation can be effectively reduced by proper design of building posture and support before laser powder bed melting.Moreover,without the data of thermophysical property variation of Ti-6Al-4V artificial knee implants with temperature,predicting the residual stress and deformation with acceptable accuracy and reduced time cost can be achieved by the inherent strain model.展开更多
An inherent strain method was applied to the welding deformation analysis of left girder of GM’s Buick’s chassis underframe assembly. Three models are used in the calculation. Model 1 takes into account the longitud...An inherent strain method was applied to the welding deformation analysis of left girder of GM’s Buick’s chassis underframe assembly. Three models are used in the calculation. Model 1 takes into account the longitudinal and transverse inherent strains; model 2 considers only longitudinal inherent strain; model 3 also takes into account the longitudinal and transverse inherent strains, but inherent strains are taken according to the function instead of the constant, for simulating the variation of the girder’s stiffness during welding process. The result shows the deformation of model 2 is less than that of the model 1, the error is less than 10% of the absolute displacement. So the longitudinal inherent strain is the main factor determining boxes-girder’s welding deformation. The deformation of model 3 is also less than that of the model 1, because the inherent strains of the model 3 are less than that of the model 1. At last, the welding deformation of the whole underframe was analyzed. The analysis results can be taken as references not only for the choices of welding sequence, welding parameters and fixture’s location, but also for welding deformation prediction of other car chassis.展开更多
基金supported by the National Key Scientific and Technological Infrastructure Construction Project(No.2018-000052-73-01-001228)National Natural Science Foundation of China Young Scientists Fund Project(12105185)Science Foundation of Institute of Plasma Physics,Chinese Academy of Sciences(No.DSJJ-2023-06).
文摘Welding is commonly employed to connect large-scale components in practical engineering.Predicting the resulting deforma-tion and residual stresses during the welding process is typically essential.The thermal-elastic-plastic method simulates the welding process by examining heat distribution and elastic-plastic stresses.Despite its high computational accuracy,this method is often time-consuming,rendering it less suitable for large component welding predictions.In contrast,the inherent strain method skips the welding process and fo-cuses on the inherent strain in the weld and joint areas post-welding.This method is fast and convenient,particularly suitable for the analysis of large and complex structures.The results show that the error rate is 4.6%when using the inherent strain method to calculate the welding deformation of the test plate.In the calculation of welded parts,the error rate is 5%,which is within the tolerance of the actual engineering.In this paper,the simulation accuracy of the deformation results of the inherent strain method is validated by simulating fusion vacuum ves-sel mockup,aiming to reduce the cost of welding analysis by using this method and to provide reference for practical welding applications.
基金Natural Science Foundation of Shandong Province(ZR2020ME020)。
文摘Through a modified inherent strain model based on the minimum residual stress and deformation,three building schemes with different building postures and support structures were evaluated by finite element analysis.Results demonstrate that according to the principle of reducing the overall height of the building and reducing the support structure with a large tilt angle from the building direction,the residual stress and deformation can be effectively reduced by proper design of building posture and support before laser powder bed melting.Moreover,without the data of thermophysical property variation of Ti-6Al-4V artificial knee implants with temperature,predicting the residual stress and deformation with acceptable accuracy and reduced time cost can be achieved by the inherent strain model.
基金Shanghai Car Industry Science and Technology DevelopmentFoundation (No.2 3 2 8A)
文摘An inherent strain method was applied to the welding deformation analysis of left girder of GM’s Buick’s chassis underframe assembly. Three models are used in the calculation. Model 1 takes into account the longitudinal and transverse inherent strains; model 2 considers only longitudinal inherent strain; model 3 also takes into account the longitudinal and transverse inherent strains, but inherent strains are taken according to the function instead of the constant, for simulating the variation of the girder’s stiffness during welding process. The result shows the deformation of model 2 is less than that of the model 1, the error is less than 10% of the absolute displacement. So the longitudinal inherent strain is the main factor determining boxes-girder’s welding deformation. The deformation of model 3 is also less than that of the model 1, because the inherent strains of the model 3 are less than that of the model 1. At last, the welding deformation of the whole underframe was analyzed. The analysis results can be taken as references not only for the choices of welding sequence, welding parameters and fixture’s location, but also for welding deformation prediction of other car chassis.