YAG wet-chemical synthesis from chlorides and nitrates precursors: effect on phase evolution and powder sinterability

The influence of inorganic precursors on phase evolution and powder sinterability of YAG has been investigated. YAG powders were synthesised by reverse-strike precipitation, from yttrium and aluminium chlorides or nitrates aqueous solution. The powders were characterised by thermal analysis and XRD measurements. Pure-YAG was obtained after calcination at high temperature from both precursors, but the chlorides-derived materials yield mixtures of YAG and metastable YAlO3 phases from 800°C to 1100°C. On the contrary, nitrates precursors led to the nucleation of pure-YAG at very low temperatures (from 500°C), thus allowing to directly produce well crystallised YAG powders, suitable for enhanced sintered products.