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Characteristics of dissimilar metal welds between ASTM Type 316L and carbon steel ASTM A516 Gr.70made with FCAW were evaluated in terms of microstructure, ferrite content, EDS analysis, hardness, tensilestrength, impact toughness and corrosion resistance. Three heat inputs of 10.4, 16.9, 23.4kJ/cm were employedto make joints of dissimilar metals with E309LMoT1-1 wire. Microstructure of dissimilar weld metals consistedof mostly vermicular type of δ-ferrite and some lathy type of δ-ferrite, and δ-ferrite was transformed intoglobular type in reheated zone. In all conditions, weld metals were solidified on FA solidification mode. Based onthe EDS analysis of weld metals, All Creq/Nieq values were in the range of FA solidification mode, and it wasdecreased with increasing heat inputs whereas it was increased with increasing layers. The amount of δ-ferrite was decreased with increasing heat input due to the difference of cooling rate, and it was increasedwith increasing layers. Accordingly, hardness and tensile strength of dissimilar metals weld joints was decreasedwith increasing heat input while impact energy was increased with increasing heat input. Corrosion test ofdissimilar metals weld joints showed that weight gain rate of heat input 10.4kJ/cm was the greatest, and thatof three heat inputs became constant after certain time.
