Welding Numerical Simulation Of The Parameters Impact On Welding Quality And The Study On Welding Database System

Numerical simulation using finite element method(FEM)is useful for the guidance of welding processes which include heat input,welding speed,robot numbers,preheating temperature,welding sequences,and the types of welding joints etc.In this thesis,two well adopted FEM commercial codes,i.e.,Ansys and Simufact Welding,are employed to numerically analyze the influence of welding processes on the fields of deformation,stresses,strain and temperature for X-type welding structures.Additionally,a database system is developed aiming at the quick searching the welding simulation results.The main contents of the study here include:(1)Using Ansys,the influences of preheating temperatures for various welding speeds,mechanical boundary conditions are numerically investigated and compared with the analytical results to verify the reliability of simulation results.(2)Using Simufact Welding,the influence of welding sequence in symmetrical/unsymmetrical X type welding structure is analyzed on the distributions of the stresses,strains and the deformations.(3)The main concerns are about the stresses along or perpendicular to the welding line.(4)To reduce the simulation time,meshing strategy is discussed to realize accurate simulation results with fewer meshes.(5)A database system including material properties,the simulation results for corresponding welding processes and welding structures is developed based on SQL Server database.This system helps with quick search.The work provides with guidance for the appropriate welding process.