%0 Journal Article
%A Pradeep, K. G.
%A Chang, K.
%A Kovacs, Andras
%A Sen, S.
%A Marshal, A.
%A de Kloe, René
%A Dunin-Borkowski, R. E.
%A Schneider, J. M.
%T Nano-scale Si segregation and precipitation in Cr 2 Al(Si)C MAX phase coatings impeding grain growth during oxidation
%J Materials Research Letters
%V 7
%N 5
%@ 2166-3831
%C London [u.a.]
%I Taylor & Francis
%M FZJ-2020-02777
%P 180 - 187
%D 2019
%X We recently reported that the columnar grain width of Cr2AlC MAX phase coatings increases during oxidation (4 h at 1120°C) by 80%, while for 0.7 at.% Si additions to Cr2AlC, coarsening of only 12% was observed. Here, we use nm scale compositional and microstructural investigations to identify significant differences between Cr2AlC and Cr2Al(Si)C. In particular, needle-shaped precipitates coarsen into globular Cr3Si precipitates upon oxidation in the Si-containing MAX phase. We infer that the presence of these precipitates, which are located predominantly along grain boundaries in the MAX phase, retards coarsening during oxidation by Zener pinning.
%F PUB:(DE-HGF)16
%9 Journal Article
%U <Go to ISI:>//WOS:000463803200002
%R 10.1080/21663831.2019.1572663
%U https://juser.fz-juelich.de/record/878325