The Effect of Mechanical Activation on the Synthesis and Properties of Multiferroic Lead Iron Niobate

Dielectric and Mossbauer Studies of Pb(Fe1/2Ta1/2)O3Multiferroic Ceramics Sintered from Mechanoactivated Powders

“…In order to compensate PbO losses during sintering, 3 wt.% excess of PbO was added to this mixture. Mechanical activation was carried out using the highenergy planetary-centrifugal ball mill AGO-2 [25,26] under a ball acceleration of 40 g. A mixture of powdered reagents (10 grams) was placed into steel cylinder together with 200 grams of steel balls 8 mm in diameter. Activation was carried out for 20 minutes.…”

“…We have recently shown that the Neel temperature T N of the antiferromagnetic phase transition in PFN powders can be changed substantially by mechanical activation and subsequent annealing [25,26]. However, there is no data on the effect of mechanical activation on the properties of PFT.…”

Phase formation on the surface of lead ferroniobate depending on the conditions of mechanochemical synthesis and sintering

“…It was demonstrated by us in [5][6][7][8] that admixture phases are formed in the surface layer of sintered samples; these phases are removed after polishing off a layer about 100 μm thick. However, chemical processes that take place on sample surface during sintering are not considered in those works.…”

“…The synthesis of lead ferroniobate involves the formation of Pb(Fe 0.5 Nb 0.5 )O 3 phase with perovskite-type structure and also the formation of Pb 2 Fe 4 Nb 4 O 21 phase with pyrochloretype structure. This is characteristic not only for the synthesis of PFN [5,6], but also for a number of other compounds with perovskite structure, for example lead zirconate-titanate [7] and for the mechanochemical synthesis of lithium niobate doped with copper [8].…”

“…The goal of the paper is investigation of the phase composition of surface layers in lithium-doped lead ferroniobate ceramics formed during thermal treatment of compacted mechanically activated mixture of reagents (Nb 2 O 5 , Fe 2 O 3 , PbO and Li 2 CO 3 ) above 650 °C, depending on the conditions of mechanical activation, filling and subsequent thermal treatment. Conditions for sample sintering were chosen by analogy with those used in [5][6][7][8]. The structures of annealed samples were considered in the same works.…”