Zircon Synthesis via Sintering of Milled SiO₂ and ZrO₂

Abstract

The formation of zircon (ZrSiO 4 ) via sintering of milled SiO 2 and ZrO 2 powders was studied, and the effects of slurry vs dry milling, sintering time, and particle size on zircon yield were examined. It was found that very high zircon yields could be obtained via slurry milling, cold pressing, and sintering of the oxide precursors. The controlling factor in determining zircon yield was found to be the particle size of the SiO 2 and ZrO 2 powders. Zircon yield as a function of sintering time was examined, and found to be similar to previous studies in which sol-gel precursors seeded with zircon were used. SEM studies reveal a homogeneous product with particle sizes on the order of 1-5 µm. It was found that complete reaction to zircon can be achieved from a once-through milling, pressing, and sintering process of SiO 2 -ZrO 2 powders.

The effect of milling additives on powder properties and sintered body microstructure of NiO

“…The observation of a more rapid decrease in particle size for dry versus wet grinding is consistent with previous work, documenting structural changes of α-Fe 2 O 3 as a function of milling environment [30]. In contrast, a more rapid decrease in particle size is observed for slurry milling of ZrO 2 as opposed to dry milling [31]. This apparent inconsistency is resolved when we consider that the zirconia study measured particle size using sedimentation.…”

High‐Temperature Corrosion of EB‐PVD Yttria Partially Stabilized Zirconia Thermal Barrier Coatings with an Artificial Volcanic Ash Overlay

“…Besides the lower intensity of the peaks associated with a plagioclase‐type phase, the formation of zircon (ZrSiO 4 ) is evident, which requires the partial decomposition of YSZ. The crystallization of ZrSiO 4 is noteworthy because this reaction is extremely sluggish in the binary ZrO 2 –SiO 2 at 1200°C 15,16 . However, the presence of additional oxides may accelerate significantly the ZrSiO 4 formation.…”

Review – Volcanic Ash and its Influence on Aircraft Engine Components

“…11b), probably due to the progressive dissolution of Y 2 O 3 from YSZ by AVA until ZrSiO 4 nucleates and grows at the interface between the Y 2 O 3 -enriched amorphous phase and the residual ZrO 2 . The reaction between ZrO 2 and SiO 2 is very slow at 1200°C [15,16]. Typically, ZrSiO 4 is located on top of the inter-columnar gaps bridging individual YSZ columns.…”