In Situ TEM Temperature Study of Solid State Reaction of Lanthanum Oxide and Chromia
Monday, 27 July 2015
Hall 2 (Scottish Exhibition and Conference Centre)
Rare earth elements like La and Ce are known to improve the corrosion resistance of coated ferritic steels [1
]. The solid state reaction between La-rich oxide and Cr2
has been studied by x-ray diffraction (XRD) and in situ heating TEM with electron diffraction. The La-rich oxide powder was found to be porous and polycrystalline and would start by healing the pores and forming a transition phase of orthorhombic CrLaO3
] before migration of La is found at the interfaces (Figure 1). After full reaction pure La2
has been observed by HRTEM in a region initially starting as porous La-rich oxide (Figure 2).
1. S. Canovic, et al., Oxidation of Co- and Ce-nanocoated FeCr steels: A microstructural investigation. Surface & Coatings Technology, 2012.
2. M.W. Lundberg, et al., Precoated AISI441 for SOFC interconnectors studied by TEM methods. ECS Transactions, 2013. 57(1): p. 2321-2329.
3. C.P. Khattak and D.E. Cox, Structural Studies of the (La,Sr)CrO3 System. Materials Research Bulletine, 1977. 12: p. 463-472.