20.500.12556/DKUM-53125 Chemical reactions between $BaTiO_3$ ceramic and fluorine-containing atmosphere Kemijska reakcija med keramiko $BaTiO_3$ in keramiko fluora ▫$BaTiO_3$▫ ceramics were exposed to fluorine-containing atmosphere prepared by introducing a fluorination agent (▫$CF_3CH_2OH$▫) into a hot alumina-tube furnace. The fluorinated samples were studied using SEM and TEM. The fluorination resulted in the formation of a surface-reaction layer with a complex structure. At the reaction front fluorine reacts with ▫$BaTIO_3$▫ to produce ▫$BaF_2$▫ and ▫$BaTi_2O_5$▫. During the course of the fluorination the ▫$BaTi_2O_5$▫ reacts further to produce ▫$BaF_2$▫ and then subsequently Ba-polytitanates with an increasing content of titanium, and then finally ▫$TiO_2$▫. Fluorine also diffuses along the grain boundaries towards the pellet's interior. The presence of the fluorine stabilises the ▫$BaTi_2O_5$▫ compound and consequently triggers its formation in the ceramic's interior in a reaction between ▫$BaTiO_3$▫ and the intergranular phase ▫$Ba_6Ti_{17}O_{40}$▫. Keramiko ▫$BaTiO_3$▫ smo izpostavili fluorovi atmosferi, ki smo jo pripravili z vpihovanjem fluorirnega sredstva (▫$CF_3CH_2OH$▫) v vročo cevno peč. Fluorirane vzorce smo analizirali z vrstično (SEM) in transmisijsko elektronsko mikroskopijo (TEM). Med fluoriranjem se je na površini keramike tvoril reakcijski sloj komplicirane strukture. Na reakcijskem čelu je fluor reagiral z zrni ▫$BaTiO_3$▫ in nastajala sta ▫$BaF_2$▫ in ▫$BaTi_2O_5$▫. S časom fluoriranja je ▫$BaTi_2O_5$▫ nadalje reagiral s fluorom v ▫$BaF_2$▫ in različne Ba-polititanate z naraščajočo vsebnostjo titana, in končno v čisti ▫$TiO_2$▫ .Razen površinske reakcije keramike ▫$BaTiO_3$▫ s fluorovo atmosfero smo opazili,da fluor prodira vzdolž mej med zrni proti notranjosti keramike. Prisotnost fluora v notranjosti keramike je stabilizirala fazo ▫$BaTi_2O_5$▫ in tako sprožila njen nastanek z reakcijo med ▫$BaTiO_3$▫ in intergranularno fazo ▫$Ba_6Ti_{17}O_{40}$▫. ceramics fluorinated ceramic samples stabilising electronic ceramics keramika fluorirani vzorci keramike stabiliziranje keramike tehnična keramika true false true Angleški jezik Slovenski jezik Znanstveno delo 2015-07-10 19:24:20 2015-07-10 19:24:20 2022-06-02 03:09:07 2021-05-10 03:34:24 2002 0 0 str. 229-241 št. 2 Letn. 49 june 2002 0000-00-00 Zaloznikova Objavljeno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 1318-0207 666 14086149 7168534 1318-0207 URN:SI:UM:DK:QOJJ3LEM Acta_Chimica_Slovenica_2002_Makovec,_Ule,_Drofenik_Chemical_reactions_between_BaTiO~_3_ceramics_and_fluorine-containing_atmosphere.pdf Acta_Chimica_Slovenica_2002_Makovec,_Ule,_Drofenik_Chemical_reactions_between_BaTiO~_3_ceramics_and_fluorine-containing_atmosphere.pdf 1 A8E7ADD9665CB3C10CE66B5F1CF2B86E fdbbc39877516f7204d0bf902ddc74994cd397aaf770a8f37a090e73263ea3c3 8584b4c6-7c0e-11eb-bb7a-00155d0001ca https://dk.um.si/Dokument.php?lang=slv&id=115431 http://acta-arhiv.chem-soc.si/49/49-2-229.pdf 1 https://dk.um.si/Dokument.php?lang=slv&id=77685 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0