Rheological properties and spray-drying behaviors of nano-SiC based aqueous slurry

The nano-SiC based aqueous slurry with 25 wt% solid content was prepared by using β-SiC nanopowder as matrix phase, TiN nanopowder as toughening phase, and Y3Al5O12 sol as dispersion medium. The rheological properties and spray-drying behaviors of the aqueous slurry were investigated. The nano-SiC based aqueous slurry had better stability, dispersion and rheological property with a typically shear thinning. The SiC and TiN nanoparticles were “parceled” or “fixed” by the Y3Al5O12 sol with network structure, which constructed a stable dispersing system. After spray-drying of this slurry, the nano-SiC based spray-dried granules had high loose density, low repose angle and homogenous compositions distribution. It was beneficial for preparing SiC-based ceramic nanocomposite.

Graphical abstractIn the nano-SiC based aqueous slurry, the SiC and TiN nanoparticles were “parceled” or “fixed” by the Y3Al5O12 sol with network structure (Fig. 1). During spray-drying of this slurry, the YAG sol was rapidly gelated to form YAG gel with the shrinking of network, and the nanoparticles are absolutely enwrapped by dried network and do not re-aggregate each other (Fig. 2).Figure optionsDownload full-size imageDownload as PowerPoint slideHighlights► We construct dispersion model of nano-SiC based aqueous slurry system. ► We built spray-drying model of nano-SiC based aqueous slurry. ► We prepare SiC-based granules with homogenous distribution and flowability.