【摘要】 系统地研究了焊接热输入对X6 5钢焊缝金属组织及性能的影响。研究结果表明 ,热输入对焊缝金属组织及性能有显著影响。对于焊缝结晶组织 ,随着热输入的增加 ,柱状晶比例减小 ,等轴晶比例增大 ,柱状晶宽度增大。对于焊缝室温组织 ,随着热输入的增加 ,先共析铁素体有所增加 ,侧板条铁素体减少 ,针状铁素体先增加 ,但当焊接热输入达到 2 0 2 2J/mm后 ,针状铁素体量反而减少。焊缝金属低温冲击吸收功随热输入的增加而增大 ,当热输入达到 2 0 2 2J/mm后 ,则随热输入的增加而减小更多还原

【Abstract】 The effect of heat input on the microstructure and properties of weld metal in X65 steel was investigated systematically.The results showed that the heat input had an obvious effect on the microstructure and properties of the weld metal.As regards the crystalline structure of weld bead,the ratio of columnar grains decreased and equiaxial grains increased with the increase of heat input,while the width of columnar crystal increased when the heat input increased.As regard the ambient temperature microstruture of weld bead,when the heat input was increased,the primary ferrite content increased,the ferrite side plate decreased,and AF initially increased and then decreased when the heat input reached 2022J/mm.The low temperature toughness of weld metal increased with the increasing of heat input at first,but when heat input reached 2022J/mm,it decreased with the increasing of heat input.更多还原