Electrochemical characteristics of dissolution for stainless steel produced by PSH-MIM process

Metal injection molding (MIM), one of the powder metallurgy processes, has attracted considerable interest because of the advantage of better formability to fabricate complex shape products without machining and welding. In this experiment, the specimens prepared by the conventional MIM process and the powder space holder-metal injection molding process (PSH-MIM process) were used, and their corrosion behaviors were investigated through the electrochemical procedures such as potendiodynamic polarization curve measurement, electrochemical impedance spectroscopy (EIS) and the coulostat method. The porous specimen prepared by PSH-MIM process was corroded more easily than the one prepared by the conventional MIM process. This is because the PSH-MIM specimen has the greater surface area than the conventional specimen. The EIS and the coulostat measurement methods were confirmed to be quite effective for the measurement of corrosion behavior of the porous materials.