| Sumario: | Powder metallurgy is an effective method for manufacturing stainless steel parts of high quality and accuracy at low cost. However, the use of sintered stainless steels is limited due to their low density, which deteriorates their corrosion resistance. The aim of this study was to determine the corrosion behavior of AISI 409Nb stainless steel specimens sintered with different contents of boron in a hydrogen atmosphere. Boron was added for promoting the formation of a liquid phase during sintering at 1150 °C, thereby achieving a reduction of porosity and increase in density, which is necessary to improve corrosion resistance. The electrochemical techniques of linear polarization resistance (LPR) and electrochemical noise (EN) were used to determine the corrosion behavior of samples with and without additions of boron after immersion in two solutions, 0.5M H2SO4 and 0.5M NaCl. The corrosion rates and the possible corrosion mechanisms in the sintered samples were determined. The results indicate that the samples with boron additions are more prone to corrosion due to chromium carbide precipitation.
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