TY  - JOUR
AU  - Vassen, Robert
AU  - Grünwald, N.
AU  - Marcano, D.
AU  - Menzler, N. H.
AU  - Mücke, R.
AU  - Sebold, D.
AU  - Sohn, Y. J.
AU  - Guillon, Olivier
TI  - Aging of atmospherically plasma sprayed chromium evaporation barriers
JO  - Surface and coatings technology
VL  - 291
SN  - 0257-8972
CY  - Amsterdam [u.a.]
PB  - Elsevier Science
M1  - FZJ-2016-01978
SP  - 115 - 122
PY  - 2016
AB  - Chromium evaporation barriers are frequently used in solid oxide fuel cells to protect the porous cathode from chromium poisoning. Volatile chromium species are generated at the operation temperature of about 600–900 °C in a humid atmosphere for chromia scale forming steels as interconnect materials. In order to reduce this effect, barrier coatings are applied, often by atmospheric plasma spraying. However, also in these coatings microstructural changes as densification and in parallel formation of large pores have been observed. In order to clarify these mechanisms plasma sprayed Mn1.0 Co1.9Fe0.1O4 (“MCF”) are deposited on ferritic steels and furthermore coated with a perovskite based contact layer as used in stack build-up. These coatings are annealed in air up to 1000 h and the microstructural changes and bending of the samples are studied. The results show increasing bending with increasing aging time. High temperature curvature measurements indicate that the amount of bending is not significantly dependent on temperature. As an explanation the creep deformation of the substrate/coating system at high temperatures due to compressive stress levels in the coating is given. The origin of the stress is related to phase changes in combination with the oxidation of the coatings. In addition, interdiffusion and densification processes are discussed.
LB  - PUB:(DE-HGF)16
UR  - <Go to ISI:>//WOS:000389687600014
DO  - DOI:10.1016/j.surfcoat.2016.02.005
UR  - https://juser.fz-juelich.de/record/283681
ER  -