Role of GB chemistry of silicon nitride based ceramics with respect to the mechanical properties - experimental and theoretical approach

0450461 - ÚFM 2016 RIV ES eng A - Abstract
Šajgalík, P. - Hnatko, M. - Gall, M. - Dusza, J. - Tatarko, P. - Chlup, Zdeněk
Role of GB chemistry of silicon nitride based ceramics with respect to the mechanical properties - experimental and theoretical approach.
14th International Conference European Ceramics Society. Toledo: ECERS, 2015. ISBN 978-84-606-9257-7.
[ECERS 14 - International Conference of the European Ceramic Society /14./. 21.06.2015-25.06.2015, Toledo]
Institutional support: RVO:68081723
Keywords : silicon nitride * mechanical properties * GB chemistry
Subject RIV: JL - Materials Fatigue, Friction Mechanics

Six different sintering aids (Lu 2 O 3 , Yb 2 O 3 , Y 2 O 3 , Sm 2 O 3 , Nd 2 O 3 and La 2 O 3 ) were used for the processing of dense Si 3 N 4 ceramics. Room temperature fracture toughness, hardness and strength showed increasing tendency when the used rare - earth element in the oxide additive changes from a large to a small rare - earth cation (i.e. from La 3+ to Lu 3+ ). Highest hardness, reasonably high fracture toughness and strength have the ceramic material with Lu 2 O 3 sintering additive. The first principle calcul ations were used for the explanation of the fracture behaviour of the composites depending on the rare earth additive. The energy of fracture was calculated with respect to the chemical composition of GB. The experimental and theoretical results will be di scussed.
Permanent Link: http://hdl.handle.net/11104/0252336