Welding Numerical Simulation And Test Based On Multi-signal Welding Heat Source Model Optimization

The heat sources in the welding process are concentrated and fast moving,which determines the non-uniform and rapid change of temperature field.The change of temperature field plays a decisive role in the metallurgy,phase transition,welding stress field and deformation in the welding process.Welding temperature field is an important research topic in the development of welding,which contains all the information of welding joints.Welding stress and deformation are important factors of welding quality,which not only determines the size and shape of welding parts,but also determines the service performance of welding parts including fatigue performance.With the rapid development of computer technology,the application of numerical simulation in welding is also very extensive.It is of great significance to combine the application of numerical simulation technology with the actual welding process.Due to the complexity of welding process,the simulation of welding temperature field and stress field is mostly based on the posterior experiments such as residual stress test and deformation test.In this paper,a data acquisition platform for welding process is constructed,which can realize real-time and synchronous acquisition of electrical signal,arc sound signal,surface image of weld pool and temperature field and stress in welding process.At the same time,the data processing and analysis of these welding process information were carried out,and the experimental data were trained by pluralization regression model,so as to predict the weld depth.The average absolute error of the prediction model was 0.0512.These parameters are important parameters for input heat source model in numerical simulation of welding process.Through the establishment of a good heat source model to simulate the welding process of temperature field and stress changes,and compared with the actual process,found that the change trend is consistent.Using the mixture of Ar and CO₂ gas shielded arc welding,the thickness of 8 mm Q235flat on a flat docking experiment,through the ANSYS Workbench software for numerical simulation of the plate butt welding process and numerical simulation to calculate the temperature field and stress change and the surface of the molten pool and the actual experimental data and photograph of a molten pool images compared to fixed numerical simulation using the measured values make it nearly conform to the actual welding process.The absolute error between the modified molten pool and the actual molten pool is 0.0381,the average absolute error of the width is 0.0329,the average absolute error of the depth is0.0541.The average absolute error between the simulated value and the actual value of the residual stress at the marked position is0.0715.The results show that the numerical simulation of the modified welding process is good.The model can be used to guide the optimization of industrial welding process and the study of temperature field and stress variation.