The potentiodynamic polarization behaviors of 16Cr-4Al and 16Cr ODS steels in 1M HNO3 solution was investigated. The mixtures of element powders were mechanically alloyed in an attrition type ball mill. The resulting mechanically alloyed powders were sealed in cans and degassed at 673K in a vacuum of 0.1 Pa. The 16Cr ODS steel presented the lowest OCP at around -0.31V with a passivity region that started at around 0.35V, while the OCP of 16Cr-4Al ODS steel was around 0V and its passivity region started at around 0.2V. The 16Cr ODS steel had the highest value at 0.1 mA/cm2 and the 16Cr-4Al ODS steel had the second lowest value following the Inconel. The 16Cr ODS showed a large fluctuation during the passivation stage. The 16Cr-4Al-ODS steel showed good corrosion resistance in nitric acid solution. The results showed that the pitting corrosion occurred during the polarization but there was no trace of intergranular corrosion.
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