The high temperature corrosion behavior of austenitic AISI 316L, ferritic AISI 434L and duplex stainless steels obtained from three different mixtures of austenitic and ferritic powders has been studied. The materials were pressed at 700 MPa and sintered in vacuum at 1250℃. Their oxidation rate was evaluated gravimetrically by cyclic oxidation tests in air at 900℃. After a transient period of faster kinetics, all the materials reach a steady state parabolic law. Oxidation resistance increases as the nickel content of the steel decreases, showing AISI 434L stainless steel the lower oxidation rate. Through X-ray diffraction experiments and scanning electron microscopy observations, the different composition of the oxides were established, depending on the composition of the base material.
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