TY  - JOUR
AU  - Röttger, A.
AU  - Weber, S.
AU  - Theisen, W.
AU  - Rajasekeran, B.
AU  - Vassen, R.
TI  - Mechanical properties of thermally sprayed Fe based coatings
JO  - Materials science and technology
VL  - 27
SN  - 0267-0836
CY  - London [u.a.]
PB  - Maney Publishing
M1  - PreJuSER-19834
SP  - 973 - 982
PY  - 2011
N1  - The authors gratefully acknowledge financial support by the Deutsche Forschungsgemeinschaft within the project 'Thermisches Spritzen von Fe-Basis MMC' (DFG project no. TH531/6-1; VA163/4-1).
AB  - The synthetic vanadinites (Pb(x)Ca(10-x))(VO4)6F2delta, 1 < x < 9, adopt a P6(3)/m apatite structure with 9.7590 (1) < or = a < or = 10.1179 (1) A and 7.0434 (3) < or = c < or = 7.4021 (1) A. The partitioning of calcium and lead over the AI(4f) and AII(6h) positions is nonstoichiometric with lead preferentially entering the larger AII site. High-resolution electron microscopy showed that samples annealed for 10 h at 1073 K are in disequilibrium with calcium- and lead-rich microdomains co-existing at unit-cell scales. For (Pb5Ca5)(VO4)6F2delta, sintering in excess of 2 weeks is required for the metals to order macroscopically. As annealing progresses, c/a, the partitioning coefficient kPb(AI/AII) and the AIO6 metaprism twist angle (phi) adjust cooperatively to enlarge the apatite channel, and thereby accommodate higher lead content. These results demonstrate that phi is a sensitive measure of disequilibrium and a useful device for monitoring changes in apatite topology as a function of composition.
KW  - J (WoSType)
LB  - PUB:(DE-HGF)16
C6  - pmid:15017085
UR  - <Go to ISI:>//WOS:000291551000001
DO  - DOI:10.1179/1743284710Y.0000000002
UR  - https://juser.fz-juelich.de/record/19834
ER  -