Analysis On Surface Residual Stress Of Different Depth Surfacing Layer

The paper based on the Q235 steel welding as the research object,and Simulated stress and strain field and the blind hole method is used to measure two ways to explore different surfacing layer thickness on the influence of welding residual stress.Through the analysis of simulation results and experimental results,has been clear about the different thickness of hardfacing layer surface residual stress distribution rule.In this paper,through the establishment of four kinds of thickness of the weld,carry on the numerical simulation in the finite element software MSC.Marc,use Marc unit and heat-structure coupling function analysis for simulation of welding process.Along the direction of weld residual stress distribution curve is given,Compare the different thickness of hardfacing layer in the longitudinal stress and strain,Determines the different thickness of surfacing welding layer on the surface of welding residual stress distribution rule.The main conclusions of surfacing layer thickness is 2 mm,3 mm,4 mm,5 mm weld longitudinal tensile stress is 191 MPa and 305 MPa,respectively 423 MPa and 628 MPa.The surface residual stress increases with the increase of surfacing layer thickness.In order to verify the simulation accuracy,milling different thickness grooves on the base of Q235 low carbon steel,With D112 manual arc surfacing electrode,get different thickness of surfacing layer,measure the residual stress value in surfacing layer with blind hole method.The experimental results for the surfacing layer thickness is 2 mm,3 mm,4 mm,5 mm weld longitudinal tensile stress is 267 MPa and 353 MPa,respectively 577 MPa and 773 MPa.The surface residual stress increases with the increase of surfacing layer thickness.Compared with the finite element simulation analysis and the measured results of the blind hole method,There is a certain gap between the two,because of surfacing material mechanics parameter Settings.However,Both have good on trend,thus finite element simulation under the condition of improving precision of material parameters,can guide the welding residual stress research.