Preparation of alumina-zirconia composites containing microfibers

0451649 - ÚFM 2016 RIV SK eng A - Abstract
Hadraba, Hynek - Chlup, Zdeněk - Drdlík, D.
Preparation of alumina-zirconia composites containing microfibers.
Engineering Ceramics 2015. Bratislava: Slovenská akademie věd, 2015 - (Lenčéš, Z.; Valúchová, J.). s. 73-73. ISBN 978-80-971648-3-6.
[Engineering Ceramics 2015. 10.05.2015-14.05.2015, Smolenice castle]
R&D Projects: GA MŠMT(CZ) ED1.1.00/02.0068; GA ČR(CZ) GA15-06390S
Institutional support: RVO:68081723
Keywords : alumina * zirconia * fibres * laminates * electrophoretic deposition
Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

The electrophoretic deposition (EPD) is a suitable shaping method for ceramic composites preparation from its early beginning. Preparation of particulate, fibre reinforced and laminate ceramic composites by EPD using either aqueous or inorganic solvents was successfully demonstrated [1-4].The aim of this work was preparation of alumina and zirconia laminates created from alternating composite layers containing alumina and zirconia micro fibres inside the layers and/or at the inter-layer interface. Electrophoretic deposition was performed from concentrated isopropanolic suspensions stabilised by monochloracetic acid containing mixture of alumina or zirconia powder and certain amount of alumina or zirconia micro fibres. Three methods of suspension preparation were studied from the point of view of micro fibre arrangement in the deposit. Firstly, the EPD was conducted using the suspension prepared from ball milled premixed micro fibre and powder dried granulate, secondly directly from the ball milled micro fibres added to the suspension containing powder and finally using the sonicated suspension of micro fibres and given powder. Method for in-situ monitoring of amount of deposited mixture of particles and micro fibres mass was developed and experimentally checked. Prediction of electrophoretic deposition kinetics was based on the voltage drop measurement and electrophoretic mobility estimation from experimental kinetics data. The influence on the fibre orientation and homogeneity was observed in accordance with method used for deposition. The optimised process of electrophoretic deposition of alumina and zirconia based composites using isopropanolic suspensions stabilised by monochloracetic acid allowed preparation of laminate consisting of strongly bonded layers containing certain amount of homogeneously distributed microfibers.
Permanent Link: http://hdl.handle.net/11104/0253000