Microwave synthesis and sintering of Ba(Mg1/3Ta2/3)O3

Abstract Ba(Mg 1/3 Ta 2/3 )O 3 , BMT, was synthesized and sintered by microwave processing at 2.45 GHz. Appropriate amounts of BaCO 3 , MgO, and non-stoichiometric Ta 2 O 5− x were used as starting materials for the synthesis. BMT was obtained by heating the precursors in a multimode microwave cavity of 2 kW between 900°C and 1300°C for just 20 min. The synthesis was carried out in N 2 atmosphere to prevent the oxidation of Ta 2 O 5− x . The perovskite BMT starts forming at 900°C and becomes single phase material at 1300°C. The sintering of BMT was carried out in a single mode microwave cavity for 5 to 30 min at 1400°C to 1600°C without using any sintering aid. A relative density of 97% was obtained in 30 min of microwave sintering at 1600°C. In contrast, it was found that to achieve the same densification, it requires 6 h of soaking at the same temperature in conventional sintering process.