CeO_2安定化正方晶ジルコニア/Al_2O_3ナノ複合材料の作製と機械的特性 Fabrication and Mechanical Properties of CeO_2 Stabilized Tetragonal Zirconia Based Nanocomposites Incorporating Al_2O_3 Dispersions
To compensate the definite disadvantages of ceria stabilized tetragonal zirconia polycrystal (Ce-TZP) as compared to Y-TZP ceramics, such as lower strength and lower hardness, we applied the idea of the nanocomposite to Ce-TZP/Al<SUB>2</SUB>O<SUB>3</SUB> composite system. Zirconia matrix in these composites consisted of primarily the tetragonal phase and a small amount of the monoclinic phase. These composites partly possessed an intragranular nanostructure, in which fine alumina particles were trapped within the zirconia grains. At an optimum component for the 10Ce-TZP/30vol% Al<SUB>2</SUB>O<SUB>3</SUB> composite sintered at 1500°C, strength of 730 MPa and very high toughness of 10.2 Mpa.m<SUB>1/2</SUB> (SEPB) were achieved. This toughness value was in excess of that (8.1 MPa⋅m<SUB>1/2</SUB>) of WC/Co cermet. Therefore, it is suggested that this composite system would be expected as candidate for an attractive TZP ceramics, which have advantages of both high strength in Y-TZP and high toughness in Ce-TZP along with high resistance to low-temperature degradation.
粉体および粉末冶金 43(4), 415-420, 1996-04-15
Japan Society of Powder and Powder Metallurgy