Phase evolution in reaction sintered zirconium titanate based materials

11 páginas, 17 figuras.-- El pdf del artículo es la versión post-print.Zirconium titanate materials are proposed for structural components for which fully reacted and relatively large pieces are required. In this work the phase evolution in slip cast compacts constituted by equimolar mixtures of TiO2 and ZrO2 stabilized with 3 mol% of Y2O3 at high temperature is studied, to establish the basis to design suitable thermal treatments for ZrO2(Y2O3)–TiO2 materials. The temperatures at which the processes involved in the reaction sintering occurred were identified by constant heating rate experiments. Phase and microstructure analyses have been performed on specimens treated at the identified temperatures and air quenched. Then the adequate temperature range to get fully reacted and dense materials has been deduced. Materials treated at 1500 ◦C to 2 h were constituted by Zr5Ti7O24 as major phase, a solid solution of TiO2 and Y2O3 in c-ZrO2 as secondary phase and a ZrO2–TiO2–Y2O3 non-stoichiometric compound with pyrochlore structure as minor phase. Pyrochlore was demonstrated to be a metastable phase at 1500 ◦C.This work has been supported by the Spanish Ministry of Education and Science under contracts MEC MAT2006- 13480 C02-01 and MAT2007-64486 C07-02. E. López-López acknowledges to Community of Madrid (Spain) and European Social Fund for economical support by CPI/0552/2007 contract.Peer reviewe

Phase evolution in reaction sintered zirconium titanate based materials

11 páginas, 17 figuras.-- El pdf del artículo es la versión post-print.Zirconium titanate materials are proposed for structural components for which fully reacted and relatively large pieces are required. In this work the phase evolution in slip cast compacts constituted by equimolar mixtures of TiO2 and ZrO2 stabilized with 3 mol% of Y2O3 at high temperature is studied, to establish the basis to design suitable thermal treatments for ZrO2(Y2O3)–TiO2 materials. The temperatures at which the processes involved in the reaction sintering occurred were identified by constant heating rate experiments. Phase and microstructure analyses have been performed on specimens treated at the identified temperatures and air quenched. Then the adequate temperature range to get fully reacted and dense materials has been deduced. Materials treated at 1500 ◦C to 2 h were constituted by Zr5Ti7O24 as major phase, a solid solution of TiO2 and Y2O3 in c-ZrO2 as secondary phase and a ZrO2–TiO2–Y2O3 non-stoichiometric compound with pyrochlore structure as minor phase. Pyrochlore was demonstrated to be a metastable phase at 1500 ◦C.This work has been supported by the Spanish Ministry of Education and Science under contracts MEC MAT2006- 13480 C02-01 and MAT2007-64486 C07-02. E. López-López acknowledges to Community of Madrid (Spain) and European Social Fund for economical support by CPI/0552/2007 contract.Peer reviewe