HQ130钢焊接区扩散氢分布的数值分析

Numerical Analysis of Diffusion Hydrogen Distrbution in Welding Zone for HQ130 High Strength Steel

用有限元法对HQ130高强钢焊接区扩散氢分布进行了模拟计算 ,分析了扩散氢对焊接裂纹的影响。编制了焊接区氢扩散的有限元程序 ,该程序中考虑了焊接线能量、温度、氢的表面逸出系数等对氢扩散分布的影响。数值分析表明 ,氢在焊缝根部熔合区附近聚集是该区域产生裂纹的重要原因。提高焊接线能量和增大氢的表面逸出系数可降低氢在焊缝表面熔合区的聚集 ,但对焊缝根部氢的聚集影响不大。HQ130高强钢焊接控制焊接线能量在 2 0kJ/cm以下可减小氢的局部聚集 ,有利于防止根部焊接裂纹的产生。

The distribution of diffusion hydrogen in welding zone of HQ130 high strength steel is calculated by using finite element method (FEM).And their effects on weld crack are analyzed.The finite element program of hydrogen diffusion in welding zone is worked out.In the program,the effects of weld heat input (E),temperature,plasticity distortion,surface escaping coefficient of hydrogen etc,on hydrogen diffusion are taken into account.The numerical analysis indicated that hydrogen accumulates seriously near the fusion zone,especially in weld root.This is an important factor to cause crack in this zone.Increasing weld heat input and surface escaping coefficient of hydrogen can decrease hydrogen accumulation in the fusion zone of weld surface,but it is not obviously sin weld root.Increasing dislocation makes hydrogen accumulate seriously in fusion zone.The results of test and analysis indicate that the heat input in the middle weld should be controlled to about 16kJ/cm to prevent crack generating and propagating for HQ130 steel.