Effect of copper content on the microstructure and mechanical properties of multipass MMA, low alloy steel weld metal deposits

Effect of copper content in the range of 0.14–0.94 wt.% on the microstructure and mechanical properties of Cr–Ni–Cu low alloy steel weld metal deposits was investigated. All welds were prepared by manual metal arc welding technique in flat position. Microstructure of the welds was examined by optical and scanning electron microscopes. The results showed increase in acicular ferrite and microphases formed at the expense of primary ferrite and ferrite with second phase with steady refinement of microstructure. According to these microstructural changes, hardness, yield and ultimate tensile stresses increased while Charpy V-notch impact toughness and percent elongation reduced.