Low-temperature fabrication of BaBi2Nb2O9 ceramics by reaction controlled sintering

Abstract

Reaction controlled sintering was applied to the fabrication of BaBi 2 Nb 2 O 9 (BBN) ceramics at lower temperature. A powder mixture of BaCO 3 and Nb 2 O 5 was heated at 600°C in a 1st step calcination to produce a binary precursor of BaNb 2 O 6 . The pre-heated powder was then mixed with a fixed amount of Bi 2 O 3 , which was subsequently pressed into a disk pellet. After a powder compact of the mixture was subjected to heating at 950°C for 4 h, a BBN bulk sample with a relative density of 92% was successfully obtained. The low-temperature fabrication of dense BBN ceramics could be attributed to the inhibited formation of an intermediate phase of Ba 5 Nb 4 O 15 and the production of submicron powder with an appropriate reactivity during a 1st step calcination.

Dielectric relaxor and conductivity characteristics of undoped and samarium doped barium bismuth niobate ferroelectric ceramics

“…Barium bismuth niobate (BBN) relaxor ferroelectrics have been recognised to be an increasingly important material for microelectromechanical and non -volatile random access memory device applications [1][2][3][4][5]. This material has a layered crystal structure consists of two NbO 6 octahedral stacked along the c-axis between two neighbouring (Bi 2 O 2 ) 2+ layers [6].…”