添加过量 Na2CO3对（Na0．5Bi0．5）0．94Ba0．06 TiO3无铅压电陶瓷结构和电学性能的影响

摘要

钛酸铋钠基陶瓷中含有易挥发性 Na＋，为研究 Na＋含量对钛酸铋钠基陶瓷结构和电学性能的影响，采用传统固相反应法制备了（Na0．5 Bi0．5）0．94 Ba0．06 TiO3＋xwt．％Na2 CO3（记为 BN6BT-xNa，x＝0、0．5、1、2）无铅压电陶瓷。研究了添加过量 Na2 CO3对（Na0．5 Bi0．5）0．94 Ba0．06 TiO3陶瓷的烧结性能、晶体结构、显微结构、压电性能、介电性能和铁电性能的影响。发现在1180℃烧结的陶瓷均具有纯钙钛矿结构，陶瓷的晶粒尺寸随 Na2 CO3含量不同而改变。钛酸铋钠基陶瓷的结构和电学性能与 Na＋含量密切相关。研究结果表明：1180℃烧结的 x＝1组分陶瓷具有最大的体密度（5．73 g／cm3），最大的压电常数（88 pC／N），较高的剩余极化强度（25．5μC／cm2）和较低的矫顽场（27．5 kV／cm）。%The Na+ is volatile in (Na0.5 Bi0.5 )0.94 Ba0.06 TiO3-based ceramics.In order to find the effects of Na+ amount on structure and electrical properties of (Na0.5 Bi0.5 )0.94 Ba0.06 TiO3-based ce-ramics,(Na0.5 Bi0.5 )0.94 Ba0.06 TiO3 +xwt.%Na2 CO3 (BN6BT-xNa,x=0,0.5,1,2)lead-free ce-ramics were prepared via conventional solid state reaction method.Effect of excess Na2 CO3 on sintering behavior,crystallite structure,microstructure,piezoelectric,dielectric and ferroelectric properties were studied.The ceramics sintered at 1 180℃ exhibit pure ABO3 perovskite struc-ture.The size of grains in the ceramics varies with the the amount of Na+ .The structure and e-lectrical properties of (Na0.5 Bi0.5 )0.94 Ba0.06 TiO3-based ceramics are tightly related to the Na+ a-mount.The ceramic with x = 1 sintered at 1 180 ℃ exhibits the highest bulk density(5.73 g/cm3 ),highest piezoelectric charge constant (88 pC/N),higher remanent polarization (25.5μC/cm2 )and lower coercive field (27.5 kV/cm).