Numerical Simulation Research On Laser-arc Hybrid Welding Based On0n Q890 High Strength Steel

In this paper,the laser-arc hybrid welding is used to simulate the Q890high-strength steel.Firstly,the workpiece is welded,according to the whole size of the weld parts,the modeling and meshing is established in Visual-Mesh.The thermophysical and thermomechanical properties of Q890 high-strength steel is simulated by Jmatpro.In view of the feasibility of Visual-Weld simulation software,it is established that three factors Orthogonal test of two levels and two indicators by us,then calculate their temperature field through Visual-Weld.Secondly,Minitab is used to analyze the temperature field to select the best combination.Finally,the stress field is calculated by Visual-Weld,and one of the excellent combinations is subjected to stress experiment.The stress distribution of the two excellent combinations is comprehensively compared,and the simulated calculated values and the experimental measured values are verified.Conclusion as below,?1?On the basis of the orthogonal experiment temperature field,combined with range and analysis of variance of Minitab,it can be seen that the preheating temperature and the interlayer temperature have a significant effect on the t_8/3and t_hof the temperature field,and the distance between the filaments is not significant.The goodness of fit of t_8/3and t_hreaches 100%,and the adjusted values are 99.99%and 99.98%,which prove that the orthogonal test model was correct.?2?By extracting the thermal cycle curves of the excellent combination temperature field,two Phenomena are summarized,?1?The temperature of the thermal cycle curve of each point of the group A1B1C1 is slightly lower than that of the group A2B2C1 due to the difference of preheating temperature.?2?When the second welding starts,the temperature of the upper surface of the modeling at different points from the weld has a different degree of decline.?3?The stress distribution is similar along the path of Path1?Path4 based on the results of the excellent combined stress field.?4?For the blind hole and X-ray stress test of the A1B1C1 group,it is found that the longitudinal stress along the weld direction is larger than the transverse stress.The measured value of the blind hole method is larger than the measured value of the X-ray method.The maximum error of the longitudinal residual stress is 8.3%.The maximum lateral residual stress error is 20%.The transverse stress in the vertical weld direction is generally tensile,while the longitudinal stress is pressed at both ends,and the middle is pulled.The measured value of the blind hole method is larger than the measured value of the X-ray method.The maximum error of the longitudinal residual stress is8.3%,and the maximum error of the lateral residual stress is 35.9%.?5?The comprehensive stress comparison of the stress conditions along Path1 and Path3 and the comparison between the measured values and calculated values of the A1B1C1 experiment.The results show that,?1?the transverse direction of the two superior combinations are pressed at both ends in the transverse direction of the weld,the middle is pulled,and the tensile stress decreases with the distance from the weld,and its decrease is smaller than the increase of the compressive stress at both ends.While the longitudinal direction is pulled,the tensile stress amplitude of A1B1C1 is higher than A2B2C1.?2?The transverse and longitudinal tensile stress amplitudes of the group A2B2C1along the Path3 are lower than those of the group A1B1C1.The transverse tensile stress takes a maximum value of about 20mm from the center of the weld,and the transverse tensile stress gradually decreases outside this area,until the edge is reduced to zero.The longitudinal stress distribution is intermediate tension and the two sides are compressed.The tensile stress amplitude is obtained at about 12mm from the center of the weld.The longitudinal tensile stress of the two ends outside the 12mm range decreases with the increase of the distance and is converted into compressive stress.?3?The stress test values of the group A1B1C1 are close to the calculated values,and the trend is consistent.