Growth mechanism of high-aspect ratio zirconia whisker by molten salt method

期刊论文
发表日期：

2024年7月16日

查看全文

Y Wang,
B Qian,
Z Li,
C G Bao,
Y Bai,
M Liu,
H D Wang,
B Wang,
F L Yu,
B B Liu,
Y T Yin,
L F Wang,
S H Huang

摘要

Regulation on one-dimensional growth has been a major challenge for the preparation of high quality zirconia whiskers. In the present work, high-aspect ratio zirconia whiskers were successfully synthesized via molten salt method. The effect of soaking time on the aspect ratio and growth behaviour of zirconia whiskers was studied. The results suggested that the average aspect ratio of zirconia whiskers reached to 42 at 15 h. The zirconia whiskers grew along [100] direction. The entire process can be divided into an initial slow stage, a rapid growth stage and a declining stage. The dissolution–precipitation of Na_9-4xZr_x(PO₄)₃ is the key factor in the initial slow stage. The rapid growth stage of zirconia whiskers is highly dependent on the directional adsorption of F⁻ and screw dislocation step. In the declining stage, the drastic transformation of whiskers morphology from fibrous shape to rod-like and granular ones is caused by excessive volatilization of Na₃PO₄·12H₂O and NaF molten salts.