Microstructure and electrochemical corrosion behavior of Q460 axle shell submerged arc weld

Q460 high strength low alloy steel and its submerged arc welded joints were chosen to study microstructure and properties of weld by metallographic microscope, scanning electron microscope (SEM), energy dispersive spectrometry (EDS) and microhardness tester. Corrosion behavior of weld was studied by electrochemical polarization curve test. The experimental results showed that microstructure of weld was needle-like ferrite and pearlite, grains of weld were the finest after quenching and high temperature tempering. Hardness of weld was greater than that of parent material. Corrosion resistance of weld was lower than that of parent material. Corrosion resistance of Q460 weld was slightly worse than that of Q510 and Q345 high strength low alloy steel in the corrosion environment NaCl with a mass fraction of 3.5%.