High temperature oxidation of a Cu-Ni – based cermet: kinetic and microstructural study

Fabien Rioult (1, 2, 3) , Michèle Pijolat (1, 2, 3) , Françoise Valdivieso (1, 2, 3) , Marie-Agnès Prin-Lamaze (4)

1 ProcESS-ENSMSE - Département Procédés et évolution des systèmes avec solides
2 SPIN-ENSMSE - Centre Sciences des Processus Industriels et Naturels
3 LPMG-EMSE - Laboratoire des Procédés en Milieux Granulaires
4 CRV - Alcan

The oxidation of a cermet composed of nickel ferrite (NixFe3-xO4), nickel oxide (NiyFe1-yO) and Ni-Cu alloy (CuzNi1-z) (with x=0.8, y=0.84 and z=0.44) has been studied by thermogravimetry, at 960°C, under controlled oxygen partial pressure. The rate of oxidation increases with the oxygen partial pressure up to 5.1 103 Pa, then it becomes independent of the oxygen pressure. This is due to the presence of the two copper oxides, CuO and Cu2O, above this oxygen pressure. SEM observation of oxidized samples has shown that the oxidation mechanism involves both external and internal oxidation.

Keywords: cermet; oxidation; mechanisms; diffusion; interfaces

Domains: Chemical and Process Engineering

Fabien Rioult, Michèle Pijolat, Françoise Valdivieso, Marie-Agnès Prin-Lamaze. High temperature oxidation of a Cu-Ni – based cermet: kinetic and microstructural study. Journal of the American Ceramic Society, 2006, 89 (3), pp.996-1005. ⟨10.1016/j.corsci.2009.01.019⟩. ⟨hal-00409342⟩