Preparation and characterization of scandia-stabilized zirconia containing additives
| Grant number: | 17/25501-3 |
| Support type: | Scholarships abroad - Research Internship - Post-doctor |
| Effective date (Start): | March 01, 2018 |
| Effective date (End): | February 28, 2019 |
| Field of knowledge: | Engineering - Materials and Metallurgical Engineering |
| Principal Investigator: | Eliana Navarro dos Santos Muccillo |
| Grantee: | Robson Lopes Grosso |
| Supervisor abroad: | Shen J Dillon |
| Home Institution: | Instituto de Pesquisas Energéticas e Nucleares (IPEN). Secretaria de Desenvolvimento Econômico (São Paulo - Estado). São Paulo , SP, Brazil |
| Local de pesquisa : | University of Illinois at Urbana-Champaign, United States |
| Associated to the scholarship: | 16/06205-1 - Characterization of nanostructured scandia-zirconia ceramics consolidated by Spark Plasma Sintering, BP.PD |
Abstract Scandia-zirconia (ScZ) has a great technological interest for solid electrolyte applications due to the highest ionic conductivity among zirconia-based ceramics. However, ScZ usually requires high temperatures (> 1600 °C) to achieve 95% relative density by conventional sintering. Fully dense nanocrystalline ScZ specimens were obtained by recently proposed deformable punch spark plasma sintering technique (DP-SPS). It has been postulated that DP-SPS method inhibits grain growth due to the low processing temperatures and eliminates isolated residual pores due to high pressure application. Samples of ZrO2 containing 6 to 20 mol% Sc2O3 were synthesized by coprecipitation, calcined, and sintered by DP-SPS at low temperatures (700 to 800 °C) and high pressures (1.5 and 2 GPa). X-ray diffraction patterns only revealed a cubic single phase in polycrystalline samples with average grain size between 8 and 20 nm. In this work, grain size dependent phase transition and mechanical properties in nanostructured ScZ will be investigated by in-situ transmission electron microscopy (TEM). Phase transitions as a function of grain size will be investigated during coarsening by high temperature in-situ TEM. Mechanical properties will be determined via in-situ TEM nanomechanical testing and Hall-Petch relationship will be verified by changing grain size for a specific composition and polymorph. Sintered samples will be carefully prepared by focused ion beam. Considering that there is scarce information about microstructure of fully dense nanostructured (< 20 nm) ceramics in the current literature, results originated from this work will represent original data with relevant scientific contribution. | |