Dislocations in YAG phase of a directionally solidified Al{sub}2O{sub}3/YAG deformed at room and high temperatures

摘要

Dislocation structures of the YAG (yttrium aluminum garnet, Y{sub}3Al{sub}5O{sub}12) phase in a directionally solidified Al{sub}2O{sub}3/YAG composite were investigated by transmission electron microscopy. In the as-grown specimen, dislocationnetworks composed of dislocations with Burgers vectors parallel to <100>, <110> and <111> were observed. In a specimen deformed at 1773 K, both dislocation networks and isolated dislocations with Burgers vector of a<100> and a/2<111> were observed butneither of them were glide dislocations. In a specimen deformed at room temperature, isolated dislocations with a Burgers vector of a/2<111> were observed. They were identified as glide dislocations lying on {110} planes.