Synthesis of nanocrystalline yttria powder and fabrication of transparent YAG ceramics

Luminescence properties of Y3Al5O12:Ce nanoceramics

“…Transparent optical ceramics (OC) of Y 3 Al 5 O 12 (YAG) garnet doped with rare-earth ions is now being considered as an alternative to bulk single crystals (SC) of these materials for laser media applications and scintillators [1][2][3][4][5]. Usually OC are obtained from initial row powders with small grain size [1,2] or from sintered YAG-based nanopowders [3,4] previously prepared by sol-gel methods [4][5][6].…”

“…Usually OC are obtained from initial row powders with small grain size [1,2] or from sintered YAG-based nanopowders [3,4] previously prepared by sol-gel methods [4][5][6]. The main differences of the properties of YAG-based OC in comparison with SC can be the relatively lower temperature of preparation of OC (about 1700-1750 1C) [1][2][3][4][5][6] than that for YAG:Ce SC obtained by melting at high (1970 1C) temperature by the Czochralski or modified Bridgman methods [7]. Therefore, OC can possess, in principle, lower concentration of Y Al antisite defects (AD), which are typical for melt-grown YAG-based SC [7][8][9][10][11].…”

Sintering to Transparency of Polycrystalline Ceramic Materials

“…Three stable phases exist in the Y 2 O 3 -Al 2 O 3 system: an orthorhombic perowskiteYAlO 3 ("YAP") with an Y/Al ratio 1:1, an alumina-rich cubic garnet Y 3 Al 5 O 12 ("YAG"), and an yttria rich monoclinic phase with composition Y 4 Al 2 O 9 ("YAM"). Wen et al, (2004) have obtained a transparent polycrystalline material with a transmittance of 63% in the visible range and 70% in the IR region, using a solid state reaction of alumina and yttria and after sintering at 1750ºC in vacuum atmosphere (see Fig. 2.1 for transparency in the IR).…”

High Energy Ball Milling of YAG Powders: Sintering Properties and Microstructural Evaluation

“…YAG has a cubic structure named garnet [1,2]. YAG single crystals are generally obtained by the Czochralski method.…”