Yttria stabilized Al 2O 3–ZrO 2 eutectic crystal fibers grown by the laser heated pedestal growth (LHPG) method

Abstract

In this work, yttria doped Al 2O 3/ZrO 2 eutectic crystal fibers were grown using the laser heated pedestal growth (LHPG) method. Two yttria concentrations (3 mol% and 9 mol% Y 2O 3) have been examined. Eutectic fibers 0.4–1 mm in diameter and up to 40 mm in length have been grown with pulling rate of 0.1–30 mm/min. The aim of this work was to obtain well-controlled microstructure from liquid phase. LHPG method allows us using of relatively high pulling rates compared with other growth methods. The optimal laser power corresponding to each concentration has been determined versus the pulling rate. Using X-ray powders diffraction at room temperature, the phases were identified as tetragonal one for zirconia and α-alumina for Al 2O 3. The fibers microstructure has been characterized by scanning electron microscope (SEM). The micro-structural pattern was irregular Chinese-script for both concentrations with a cellular arrangement for the higher concentration.