掺杂钛锡酸钡基陶瓷的制备及电性能研究

Preparation and Electrical Properties of Doped Barium Titanate Based Ceramics

采用固相合成工艺制备了Li-Al(简称LA)掺杂Ba1-x(LA)x(Ti_(0.91)Sn_(0.09))O_(3)-0.6%MnO_(2)陶瓷,研究了LA掺杂量对钛锡酸钡基陶瓷物相组成、相对密度、晶粒尺寸、介电性能和压电性能的影响。结果表明,LA掺杂钛锡酸钡基陶瓷都为ABO3型钙钛矿结构,(022)和(200)晶面的衍射峰会随着掺杂量增加而逐渐右偏移;随着掺杂量x从0增加至2.5%,LA掺杂钛锡酸钡基陶瓷的相对密度先增后减,在x=0.5%时取得最大值(93.7%)。相同频率下LA掺杂钛锡酸钡基陶瓷的介电常数从大至小顺序为:0.5%>1.0%>0>1.5%>2.0%>2.5%;LA掺杂量为0.5%时钛锡酸钡基陶瓷的介电常数最高。随着LA掺杂量从0增加至2.5%,压电系数d33、平面机电耦合系数Kp和相位角θmax都表现为先增后减趋势,在x=0.5%时取得最大值。x=0~1.0%时LA掺杂钛锡酸钡基陶瓷具有较好的压电温度稳定性和较高的退极化温度。钛锡酸钡基陶瓷中适宜LA掺杂量为0.5%。

Li-Al(LA)doped Ba1-x(LA)x(Ti_(0.91)Sn_(0.09))O_(3)-0.6%MnO_(2) ceramics were prepared by the solid-state synthesis method.The effects of LA doping on the phase composition,relative density,grain size,dielectric properties and piezoelectric properties of BaTiSnO3-based ceramics were studied.The results show that LA-doped barium titanate stannate based ceramics exhibit an ABO3-type perovskite structure,and the diffraction peaks of the(022)and(200)crystal planes gradually shift to the right with increasing doping amounts.With an increase in LA doping level(x)from 0 to 2.5%,the relative density of LA-doped barium titanate stannate based ceramics initially increased and then decreased,reaching a maximum value of 93.7%at x=0.5%.At the same frequency,the order of the dielectric constant of LA-doped barium titanate stannate based ceramics is:0.5%>1.0%>0>1.5%>2.0%>2.5%,with the highest dielectric constant observed at x=0.5%.As the LA doping amount increased from 0 to 2.5%,the piezoelectric coefficient d33,planar electromechanical coupling coefficient Kp and phase angleθmax showed an increasing and then decreasing trend,reaching maximum values at x=0.5%.When x=0~1.0%,the LA-doped barium titanate stannate based ceramics demonstrate favorable piezoelectric temperature stability and a higher depolarization temperature.Therefore,the appropriate amount of LA doping for barium titanate based ceramics was found to be 0.5%.