Degradation Behaviour of HR-120 Alloy Exposed to CH4-CO-H-2-H2O Mixed-Gas Environments at 950 degrees C

K. E. Tillous (1) , Jacky Dulcy (1) , Thierry Belmonte (1)

1 IJL - Institut Jean Lamour

The HR-120 alloy is a candidate structural material for heat-exchanger reactors of steam methane reforming. Consequently, the behaviour at high-temperature of this alloy in oxidizing/carburizing atmosphere is of considerable interest for industrial applications. In this study, the behaviour of HR-120 alloy was evaluated in Ar, CH4, CO, H-2, H2O oxidant/carburizing gas mixtures at 1,223 K, with or without pre-oxidation. In the former case, the as-grown scale layer consisted of inner Cr2O3 layer and an outer MnCr2O4 spinel layer. This scale structure, which is completely transformed into carbide layer in Ar-CH4 atmosphere, exhibits an excellent stability in CH4, CO, H-2, H2O gas mixture. However, the oxidation of particles rich in Nb promoted cracking and spalling of protective scale layer, resulting in exposure of substrate metal.

Domaines: Génie des procédés

K. E. Tillous, Jacky Dulcy, Thierry Belmonte. Degradation Behaviour of HR-120 Alloy Exposed to CH4-CO-H-2-H2O Mixed-Gas Environments at 950 degrees C. Oxidation of Metals, 2014, 82 (3-4), pp.163-179. ⟨10.1007/s11085-014-9484-5⟩. ⟨hal-01285991⟩