JOSE OCTAVIO ARMANI PASCHOAL
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Artigo IPEN-doc 29513 Room temperature plasticity of zirconia-yttria-titania ceramics2022 - USSUI, VALTER; LAZAR, DOLORES R.R.; LIMA, NELSON B. de; ARATA, ANELYSE; RIBEIRO, FABIO N.; DALPIAN, GUSTAVO M.; MARCHI, JULIANA; PASCHOAL, JOSE O.A.Yttria-stabilized tetragonal zirconia (Y-TZP) ceramics have excellent mechanical properties. However, such materials cannot undergo plastic deformation at room temperature due to their high hardness and brittleness values, hindering machinability. To overcome these limitations, we propose a zirconia-yttria-titania ceramics, based on zirconia containing 3mol% yttria and up to 15mol% titania. The zirconia-yttria-titania powders were synthesized by co-precipitation method, uniaxially pressed and sintered at 1400°C/5 h. Sample characterizations were carried out by X-ray diffraction, scanning electron microscopy and mechanical properties through Vickers hardness and toughness measurements. Compared to the Y-TZP ceramics, the yttria stabilised tetragonal zirconia ceramics co-doped with 10mol%Ti showed noticeable increase of tetragonality parameter, higher toughness and lower hardness values, indicating plasticity at room temperature. Furthermore, the atomistic simulation by Density Functional Theory methodology suggests the occurrence of spatial arrangement of the atoms, explaining the proposed plasticity.Resumo IPEN-doc 14790 Cinetica de sinterizacao do composito de NiO-YSZ obtido pela rota de coprecipitacao2009 - YOSHITO, W.K.; RESTIVO, T.A.G.; USSUI, V.; LAZAR, D.R.R.; PASCHOAL, J.O.A.Resumo IPEN-doc 02849 Aplicacao da tecnica de destilacao azeotropica na sintese de pos ceramicos a base de zirconio1996 - USSUI, V.; LAZAR, D.R.R.; MENEZES, F.; MENEZES, C.A.B.; PASCHOAL, J.O.A.Resumo IPEN-doc 02836 Caracterizacao eletrica de ceramicas de zirconia coprecipitadas com 8, 10, 15, 20 e 25 mol porcento itria1995 - LEITAO, F.; USSUI, V.; PASCHOAL, J.O.A.; FRANCA, Y.V.; MUCCILLO, E.N.S.; MUCCILLO, R.Resumo IPEN-doc 04400 Sintese de ZrO sub(2)-Y sub(2) O sub(3) por co-precipitacao1992 - USSUI, V.; LEITAO, F.; GENOVA, L.A.; PASCHOAL, J.O.A.Resumo IPEN-doc 05436 A influencia da variacao de temperatura de calcinacao nas caracteristicas de ZrOsub(2)-Ysub(2)Osub(3) 3 mol porcento1994 - USSUI, V.; LEITAO, F.; PASCHOAL, J.O.A.Resumo IPEN-doc 04589 Obtencao experimental da zirconia estabiblizada com itria em escala de laboratorio ampliada1993 - USSUI, V.; LEITAO, F.; GENOVA, L.A.; PASCHOAL, J.O.A.Resumo IPEN-doc 04588 Estudo de algumas variaveis do processo de sintese da zirconia estabilizada com itria por coprecipitacao1993 - USSUI, V.; LEITAO, F.; PASCHOAL, J.O.A.Resumo IPEN-doc 16164 Cinetica de sinterizacao dos pos de NiO-YSZ sintetizados pela tecnica de combustao2010 - YOSHITO, W.K.; RESTIVO, T.A.G.; USSUI, V.; LAZAR, D.R.R.; PASCHOAL, J.O.A.Resumo IPEN-doc 16166 Sinterabilidade de pos de NiO-YSZ sinterizados pela tecnica de combustao2010 - YOSHITO, W.K.; RESTIVO, T.A.G.; USSUI, V.; LAZAR, D.R.R.; PASCHOAL, J.O.A.