Effect of Ti and Mn on Microstructure and Mechanical Properties of Q690 Steel SMAW Deposited Metal

For developing welding materials matched with Q690 high strength steel, the effects of Ti and Mn contents on the microstructure and mechanical properties of the shielded metal arc welding (SMAW) deposited metal were studied by means of scanning electron microscope and energy spectrum analysis.The results show that Ti and Mn can effectively improve the microstructure and mechanical properties of deposited metal.Appropriate addtion of Ti and Mn can cause the formation of acicular ferrite in the deposited metal.With the increase of Mn content, the microstructure of the deposited metal transforms from granular bainite + acicular ferrite to lath bainite + martensite, which leads to an increase in tensile strength and a decrease in impact performance.