The phase stability of sintered composites in Al2O3-ZrO2-Y3Al5O12 system
Radosław Lach, Agnieszka Dudek, Olga Godek, Annamaria Duszová, Magdalena Ziąbka, Zbigniew Pędzich
Quarterly No. 3, 2014 pages 145-149
DOI:
keywords: sintering, mechanical properties, Al2O3, YAG, ZrO2
abstract In recent years the technology of manufacturing dense composite sinters with submicrometric grains in the alu-mina/yttria-alumina garnet (Al2O3-Y3Al5O12) system has developed. The garnet grains are very uniformly di-stributed in the alumina matrix due to applying special chemical methods. Such a material shows a higher hardness, comparable fracture toughness and almost a one order of magnitude lower wear susceptibility when compared to alumina sinters. The drawback of this material is its relatively low strength. This work presents the results of experiments on improving the mechanical properties of the Al2O3-Y3Al5O12 (YAG)m composite by introducing grains of another phase (tetragonal zirconia) into the alumina matrix. The sintering of such a com-position demanded temperature conditions which did not exclude the possibility of yttria atom diffusion betwe-en the garnet and zirconia grains. This phenomenon strongly influenced the phase composition of the final sin-ters. The paper discusses the microstructure of the sinters. The influence of the starting composition and sintering conditions on the final phase composition and selected mechanical properties of sinters were investiga-ted.