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This paper covers a study on the oxidation behavior in air of four materials processed by means of powder metallurgy (PM), in such a manner that their porosity will be high and so they can be used to manufacture anodic supports in solid-oxide fuel cells (SOFC). For this, powders with a Fe base (AISI 430L and Fe22Cr grades) and with Ni base (Ni20Cr and Ni625 grades) have been processed through a novel method specifically designed for this type of applications. The oxidation kinetics of the four materials has been studied during their exposure to high temperature, and the oxides formed both inside and on the samples have been characterized. The protective abilities of the oxides formed depend on the chromium losses during sintering of the outer surface, the oxygen diffusion rate during hightemperature exposure and the irregularities on the morphology caused by the processing method. The results of these studies have allowed to reach the conclusion that, from amongst the materials tested, Fe22Cr exhibits the best behavior in air at 800°C.

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In this work, ultrahigh carbon steels (UHCS) obtained by powder metallurgy with CIP and argon sintered at 1150°C. Then, they were rolled at 850 °C with a reduction of 40 %. Finally, steels were quenched at 850 and 1000 °C in oil. In each step, hardness, bending strength and wear performance were evaluated. Obtained results are justified with a metallographic study by SEM. Both mechanical properties and wear resistance are highly favoured with the thermomechanical treatment that removes the porosity of the material. Moreover, final quenching highly hardens the material. The obtained material could be used as matrix for tool steels.