Effects of Ti addition on the microstructure and mechanical properties of multi-pass E6010 high-cellulosic electrode weld metal

The aim of the present research was investigating the effects of Ti addition on the microstructure and mechanical properties of the E6010 high cellulosic electrode weld metal. Different concentrations of ferrotitanium were added to the electrode coating. Then, the effects of recovered Ti on the microstructure, tensile strength, hardness and impact strength of the weld metal were explored. Results showed that the recovery percent of Ti was below 10%. However, the Ti added to the melt altered the microstructural constituents and different ferrite morphologies including acicular ferrite, Widmanstatten ferrite, polygonal ferrite, and ferrite with secondary phase aligned along with the bainitic microstructure were developed at various Ti concentrations. Also, the addition of Ti improved hardness, tensile strength and yield strength while it deteriorated elongation and impact strength of the weld deposit. Finally, it was postulated that the Ti concentration in the weld metal should be lower than 0.065wt% to achieve a deposit satisfying AWS A5.1 standard requirements.