Ceramic matrix composite dispersed with metallic particles, called M(p)-CMC(s), are being developed for optimizing several functions of industrial components in severe atmospheres at high temperature.The corrosion of a model M(p)-CMC(s), based on 304L stainless steel and yttrium doped zirconia (304L(p)-ZrO2(s); 40%/60% in volume) is studied and compared with the oxidation behaviour of the stainless steel powders. The oxidation behaviour of the model 304L(p)-ZrO2(s) composite produced by powder metallurgy, studied by means of the thermogravimetry under 20 % O2 in helium at 800 °C, is presented. Oxidation curves show a fast increase in mass gain followed by slow one for the composite material. SEM observations and Auger spectroscopy measurements of the oxidized composite indicate an outward complex Cr and Fe rich oxide layer whereas Cr2O3 nodules are observed to nucleate and develop inward. For 304L stainless steel powder, the shape of the mass gain curve is parabolic, in agreement with a diffusion controlled oxidation. SEM observations of oxidised powder and in situ XRD measurements at 800 °C under oxygen show an external growth of Cr2O3 oxide layer.The low resistance to oxidation of the composite (compared to the powder) in the initial period seems to be due to the properties of the zirconia/metallic particles interface obtained after the sintering process. Under reducing conditions, the initial Cr2O3 layer reacts with zirconia matrix. TEM observation of the “as sintered” interface between the metallic particles and the ceramic shows no chromia layer. Sudden changes in oxygen partial pressure during experiments reveal an accelerating effect of the oxygen pressure.
