Oxidation mechanism of a Fe–9Cr–1Mo steel by liquid Pb–Bi eutectic alloy (Part I)

• DOI: 10.1016/j.corsci.2008.06.050
• Publication Date: 2008-07-18T08:42:34Z
• Authors: L. Martinelli; F. Balbaud-Célérier; A. Terlain; S. Delpech; G. Santarini; J. Favergeon; G. Moulin; M. Tabarant; G. Picard
• Keywords: [CHIM.MATE] Chemical Sciences/Material chemistry; A. OxygenA; [CHIM.MATE]Chemical Sciences/Material chemistry; 02 engineering and technology; 530; 01 natural sciences; Diffusion; Fe–9CrB; [CHIM] Chemical Sciences; 0103 physical sciences; Pb–BiA; [CHIM]Chemical Sciences; Oxygen tracer experimentC; 0210 nano-technology

Abstract This paper is the first part of a global study on the oxidation process of a Fe–9Cr–1Mo martensitic steel (T91) in static liquid Pb–Bi. It focuses on the oxygen transport mode across the oxide scale. The oxide layer has a duplex structure composed of an internal Fe–Cr spinel layer and an external magnetite layer. Oxygen 18 tracer experiments are performed: they show that the magnetite layer grows at the Pb–Bi/ oxide interface whereas the Fe–Cr spinel layer grows at the metal/oxide interface. Oxygen seems to diffuse across the oxide scale dissolved inside nanometric lead penetrations called nano-channels. Specific experiments are performed to characterize the nano-channels.