HCx(R) PM stainless steels were designed for applications where high wear and corrosionrnresistance are required, as the microstructure after sintering is formed by a homogeneousrndistribution of chromium-rich carbides in a stainless steel matrix. This material was diluted orrnmixed with powders of two stainless steels, one ferritic (AISI 430) and the other onernaustenitic (AISI 316), to improve its processability and properties. The corrosion resistance ofrnthis type of steel is an interesting property to study since it is probably influenced by therncarbide content dispersed in the stainless steel matrix. The corrosion resistance of allrndeveloped materials was evaluated by potenciodynamic polarization, taking as a referencernthe behaviour of the base material. The measurements were carried out after differentrnimmersion times in an aqueous NaCl solution at room temperature. Potentiodynamic testsrnyield information on kinetic aspects of the corrosion process through metallic materialrnpolarisation processes. This technique allows the determination of the corrosion potentialrn(Ecorr), the pitting nucleation potential (Enp) and the potential range where the material isrnpassive to electrochemical corrosion (Enp-Ecorr). The oxidation resistance was studied byrnheating in air at different temperatures, up to 800 ℃, during 10 days, and evaluating the gainrnmass. In both cases a microstructural study helps to understand the mechanisms involved.
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