Open AccessColloidal processing and characterization of TiO 2 –MnO‐doped alumina/alumina slurries and tapes
Author(s) -
Daniel Barros Marcelo,
Hotza Dachamir,
Janssen Rolf
Publication year - 2021
Publication title -
international journal of ceramic engineering and science
Language(s) - English
Resource type - Journals
ISSN - 2578-3270
DOI - 10.1002/ces2.10087
Subject(s) - materials science , agglomerate , scanning electron microscope , chemical engineering , dopant , colloid , slurry , thermal decomposition , doping , thermal stability , composite material , chemistry , organic chemistry , optoelectronics , engineering
Aqueous slurries of alumina doped with manganese and titanium oxides were developed. The powders and tapes were investigated by scanning electron (SEM) microscopy, X‐ray diffractometry (XRD), and thermal analyses (TG/DSC). The stability and rheology of colloidal suspensions of undoped and doped alumina suspensions were investigated. At neutral pH of 7, pure alumina and MnO–TiO 2 dopant particles present positive and negative surface charges and are prone to heterocoagulation. Optimized colloidal processing through proper adjustment of parameters was achieved to reach particle stabilization. The surface charge of the oxide particles was negative, and the suspensions did not agglomerate at a pH of 7 and higher. Tapes were cast, dried, and burned out. The thermal analyses revealed the release of residual water and decomposition of short‐chain organics at temperatures under 215°C and of long‐chain additives over 300°C.