Influence of Ni on Structure and Performance of Welding Joints of ASTM A572GR.65 Steels
The research developed the technology which impoved the mechanical performance and structure of welding joints of the ASTM A572GR.65 steels by adding Ni into them.At the same time,the reasons were made through mechanical performance tests and metallographic observations.Conclusions are made as follows: after the Ni is added into the welding joints of ASTM A572GR.65 steels,crystal structures in the seams is refined,the proportion of volume content between the acicular ferrite and the pro-eutectoid ferrite rises.For these reasons,the impact toughness is largely strengthened while the tensile strength and HV hardness improve.The research also lies the foundations for exploring welding consumables matching the ASTM A572GR.65 steels.