Synthesis of porous Al₂O₃/ZrO₂nanocomposites by chemical vapour deposition

Abstract

Al 2 O 3 /ZrO 2 one-dimensional nanocomposite structures were synthesised by chemical vapour deposition using Al 2 O 3 nanowires and a ZrCl 4 powder source at a temperature of 800 °C and a pressure of 130 Pa. The samples were characterised using X-ray diffraction, the scanning electron microscopy, the transmission electron microscopy, and N 2 adsorption-desorption. The results revealed that Al 2 O 3 /ZrO 2 composite nanowires coated with surface-embedded ZrO 2 nanocrystals were formed and that the ZrO 2 macroporous and mesoporous structures changed as the ZrO 2 deposition time increased. The pore structure and surface area were also elucidated from the N 2 adsorption-desorption measurements.

A new strategy to prepare alumina-zirconia composite or multilayered coatings by combining cold-spray deposition and plasma electrolytic oxidation

“…Nowadays, aluminazirconia ceramics have attracted significant attention in many fields such as cutting tools, bearings, hip protheses and dental implants [28,29] or even thermal barrier coatings (TBCs) for hot section components of engines [30,31]. In recent years, many techniques have been used to synthesize Al 2 O 3 -ZrO 2 composite coatings with varying morphologies and compositions, such as physical vapor deposition (PVD) [32,33], chemical vapor deposition (CVD) [34], atmospheric plasma spray (APS) [35,36], high velocity oxy fuel (HVOF) [18], spark plasma sintering [37] and sol-gel [38,39]. However, the coatings formed by these techniques are usually thin (between 100 nm and 5 µm) and/or have relatively low adhesion strength [40].…”