Fabrication of transparent LaAlO_3/t-ZrO_2 nanoceramics through controlled amorphous crystallization

摘要

Transparent nanoceramics are attracting more and more interests recently, while it is practically difficult to prepare by conventional sintering process because of undesirable grain growth. In this study a new method of amorphous sintering followed by controlled crystallization (ASCC) was developed, and transparent LaAlO_3/t-ZrO_2 nanoceramics were prepared as examples. Glass powders from Al_2O_3-La_2O_3-ZrO_2 (ALZ) were synthesized, sintered, and then converted to nanoceramics by post-heat-treatment. The processes of hot pressing and controlled crystallization were investigated in detail. The heat-treatment performed at 1200 °C for 2 h produced a transparent LaAlO_3/t-ZrO_2 nanoceramic with an average grain size of 40 nm.