Study of corrosion resistance of 17-4 PH stainless steel as-sintered and heat-treated samples manufactured by Bound Metal Deposition?

The corrosion resistance of 17-4 PH stainless steel samples additive manufactured by Bound Metal Deposition (TM) (BMD) has been investigated in neutral sodium chloride environments. The methods used in this study were based on longterm monitoring of the Open Circuit Potential and afterwards recording of Cyclic Potentiodynamic Polarization curves in the same electrolytic solution. The electrochemical investigations have been carried out on 17-4 PH wrought samples and on BMD as-sintered and H900 heat-treated samples. The BMD samples had different build-up orientations with respect to the build plate. The results showed that the susceptibility to localized corrosion of the 3D printed samples is higher than the wrought 17-4 PH, although the breakdown potential on the anodic curves was even higher in some of the former than the latter. A better corrosion behavior of the BMD printed samples was observed after heat treatment, in particular for those with build-up orientation of 0 degrees and 45 degrees.