AI Taotao ,FENG Xiaoming
(Department of Materials Science and Engineering, Shaanxi University of Technology, Hanzhong 723003)
Abstract: In-situ Al2O3 whiskers were synthesized at 1220 ℃ for 30 minutes in the static atmosphere by using Ti, Al and Nb2O5 as the starting materials. The composition of the sample and the morphology of Al2O3 whiskers were characterized by XRD,SEM and EDS analysis. The growth mechanism of Al2O3 whiskers was also analyzed. The results indicate that whenNb2O5content is low, the whiskers are long and straight and the diameter is about 30 -90 nm. Al2O3 whiskers grow via VLS mechanism, but there are some different from VLS mechanism: liquid Al acts as catalyst and key raw matters for growingAl2O3 whisker. As Nb2O5content increases, Al2O3whiskers are rough and show beads -shaped structures. So, excessiveNb2O5 content is not in favor of the growth Al2O3 whiskers.
Keywords: Al2O3 whisker, in situ, growth mechanism