Fabrication and characterization of Nb₂O₅‐doped 3Y‐TZP materials sintered by microwave technology

Abstract

The purpose of this research is focused on the manufacture and characterization of a partially stabilized zirconia ceramic with 3 mol% of Yttria and doped with .5 and 1.5 mol% of Nb 2 O 5 to analyze the influence of doping, with the purpose of improving the properties before hydrothermal degradation. In the first instance, the microwave sintering process was used for the consolidation of this material, then the physical and mechanical properties were characterized. Together, the results obtained by the conventional sintering process were compared. A low hydrothermal degradation study (LTD) is presented at low temperatures in which possible changes in the mechanical properties of the ceramic materials are analyzed and its influence on the phase transformation that zirconia may present is observed. The mechanical properties were evaluated through hardness, fracture toughness, and Young's modulus tests. Likewise, their density was analyzed, and microstructure was characterized by FESEM. It was found that the microwave-sintered samples at 1200 • C exhibited superior properties of toughness than even samples sintered by conventional methods at higher temperatures (1400 • C). The sample of 3Y-TZP with 1.5 mol% Nb 2 O 5 sintered by microwave with <.2% of porosity achieved a maximum fracture toughness value around 40% higher than the dense monolithic 3Y-TZP material.

Design and Development of Zirconia-Alumina Bioceramics Obtained at Low Temperature through Eco-Friendly Technology

“…The sintering of the samples was carried out using two different techniques: microwave technology (a non-conventional fast technique) and conventional oven. Microwave sintering (MW) has been performed in a single-mode circular cavity microwave oven operating in the TE 111 mode with a resonant frequency of 2.45 GHz (Figure 1, [27]). The microwave sintering conditions have been 1300°C of maximum temperature during 10 min of dwell time and 50°C/min of a heating rate.…”