Al2O3/ZrO2/Y3Al5O12 Composites: A High-Temperature Mechanical Characterization
AbstractAn Al2O3/5 vol%·ZrO2/5 vol%·Y3Al5O12 (YAG) tri-phase composite was manufactured by surface modification of an alumina powder with inorganic precursors of the second phases. The bulk materials were produced by die-pressing and pressureless sintering at 1500 °C, obtaining fully dense, homogenous samples, with ultra-fine ZrO2 and YAG grains dispersed in a sub-micronic alumina matrix. The high temperature mechanical properties were investigated by four-point bending tests up to 1500 °C, and the grain size stability was assessed by observing the microstructural evolution of the samples heat treated up to 1700 °C. Dynamic indentation measures were performed on as-sintered and heat-treated Al2O3/ZrO2/YAG samples in order to evaluate the micro-hardness and elastic modulus as a function of re-heating temperature. The high temperature bending tests highlighted a transition from brittle to plastic behavior comprised between 1350 and 1400 °C and a considerable flexural strength reduction at temperatures higher than 1400 °C; moreover, the microstructural investigations carried out on the re-heated samples showed a very limited grain growth up to 1650 °C. View Full-Text
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Palmero, P.; Pulci, G.; Marra, F.; Valente, T.; Montanaro, L. Al2O3/ZrO2/Y3Al5O12 Composites: A High-Temperature Mechanical Characterization. Materials 2015, 8, 611-624.
Palmero P, Pulci G, Marra F, Valente T, Montanaro L. Al2O3/ZrO2/Y3Al5O12 Composites: A High-Temperature Mechanical Characterization. Materials. 2015; 8(2):611-624.Chicago/Turabian Style
Palmero, Paola; Pulci, Giovanni; Marra, Francesco; Valente, Teodoro; Montanaro, Laura. 2015. "Al2O3/ZrO2/Y3Al5O12 Composites: A High-Temperature Mechanical Characterization." Materials 8, no. 2: 611-624.