A facile route for producing spherical granules comprising water reactive aluminium nitride added composite powders

摘要

In this contribution, a simple and cost-effective spray-granulation process has been developed for pro- ducing spherical, ready-to-press (RTP) granules comprising highly water reactive powder like aluminium nitride along with other powders such as silicon nitride, aluminium oxide and yttrium oxide for produc- ing SiAlON product. The novelty of this process stands on the instantaneous drying of granules at ambient temperature without the requirement of additional drying set-up. The salient properties of granules such as apparent density, tap density, Carr index, and Hausner ratio were evaluated. The Hall flow measure- ment shows good gravimetric flow of granules. The resultant granules which were used for producing complex shaped product with the help of cold isostatic pressing, showed good compaction behaviour as it is evident from green density of the product (approximate to 55-59% of theoretical density) and from good com- paction ratio (2.7:1). The X-ray diffraction pattern confirms that crystalline phase of sintered sample cor- responds to beta-SiAlON.