Effect of Li₂O and PbO Additions on Abnormal Grain Growth in the Pb(Mg_1/3Nb_2/3)O₃–35 mol% PbTiO₃ System

Abstract

Abnormal grain growth in Pb(Mg1/3Nb2/3)O3–35 mol% PbTiO3 (PMN‐35PT) ceramics doped with Li2O and PbO has been investigated. Replacing the PbO dopant with up to 2 mol% Li2O caused an increase in the number of abnormal grains. For the composition containing 2 mol% Li2O and 6 mol% PbO, the amount of abnormal grain growth decreased with increasing sintering temperature. Single crystals of ∼6 mm × 6 mm × 2 mm thickness were grown from the 2 mol% Li2O, 6 mol% PbO‐containing composition via the templated grain growth method. Grain growth behavior with temperature is explained in terms of the effect of Li2O on interface‐reaction‐controlled grain growth and the critical driving force.

Growth of potassium sodium niobate single crystals by solid state crystal growth

“…A bimodal microstructure develops consisting of fine matrix grains and a few large grains, often hundreds of microns in diameter. Examples of systems which display abnormal grain growth include Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 [11], Al 2 O 3 [17] and BaTiO 3 [18]. In the case of solid state crystal growth, the seed crystal acts like a large grain.…”

“…For such systems, theories of interface reaction-controlled growth are useful for describing the grain growth behaviour. Such theories were originally developed to describe the growth of crystals from solution [22] but have been used to qualitatively describe abnormal grain growth behaviour in both solid state [23,24] and liquid-phase sintered ceramics [11,25,26].…”

“…The sample is then sintered or annealed and a single crystal grows using the seed crystal as a template. This method has been used to grow single crystals of Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 [10,11] and BaTiO 3 [12]. Because solid state crystal growth uses a ceramic processing route, it is easier to grow crystals of materials which melt incongruently or have volatile elements [13].…”

Microstructural changes in (K0.5Na0.5)NbO3 ceramics sintered in various atmospheres

“…12,[21][22][23][24] If G C G max , no grains will have G > G C and grain growth rates will be negligibly slow, i.e., stagnant grain growth occurs. If G C ≤ G max , then most grains will be growing slowly or not at all, but a small number of grains will have G > G C and will be able to grow rapidly to form abnormal grains.…”

Effect of Interface Structure on the Microstructural Evolution of Ceramics

“…In the case of Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 (PMN-PT) ceramics. [135][136][137][138][139][140][141] , however, the grains even with a single twin grow preferentially and lead to AGG. Indeed, AGG occurring during the sintering of PMN-PT has been extensively studied to make a single crystal in a cost-effective way.…”