2019 Pittsburgh AISTech

In-Situ Observation and Formation Mechanism of Iron Surface Oxidation in the Initial Stages at 1,150°C (Room 306)

06 May 19
10:30 AM - 11:00 AM

Tracks: Hot Sheet Rolling

Speaker(s): P. Chris Pistorius, POSCO Professor of Materials Science & Eng., Carnegie Mellon University; Bryan Webler, Professor, Carnegie Mellon; Ming Zhong, Carnegie Mellon University; Yining He, Carnegie Mellon University; Elyce Milligan, Carnegie Mellon University

This study examined the evolution in surface morphology during initial stages of iron and steel oxidation. Polished samples were oxidized from 2 to 120 seconds in dry air at 1,150°C. Scanning electron microscopy (SEM) was used to characterize the surface morphology and the oxide layer thicknesses. x-ray diffraction (XRD) was used to confirm the surface phases. Oxide thickness increased parabolically with time. Magnetite and hematite layers were found on the wüstite layer. A dynamic oxidation process was observed, with several changes to the surface morphology occurring over the oxidation period. Possible explanations for these changes will be discussed.