【摘要】 研究了添加不同剂量锰对(Bi1 2Na1 2)TiO3-BaTiO3(BNBT)二元系的介电、压电性能的影响.发现居里温度随锰掺杂量的增加而明显下降并逐步趋于稳定.当0≤x≤0.3时,介电性能随x的增加明显加强,在x=0.3时介电常数达到1850;当x>0.3时介电性能降低.压电常数d33、kt也表现出类似的变化趋势.另外,实验发现在该体系中添加适量Mn,可在较低的极化场强下得到较高的机电耦合系数,表明掺适量锰可以有效降低矫顽场强.更多还原

【Abstract】 The dielectric, ferroelectric, piezoelectric properties of the (Bi_1/2Na_1/2)TiO₃ -BaTiO₃ binary system doped with Mn（abbreviated to BNBT-x%wt Mn） were studied. The results show that the Curie temperature T_C decreases rapidly with increasing amount of doped Mn. Dielectric constant increases at first and takes the maximum value at about 0.3 % Mn then decreases rapidly.Piezoelectric constant d₃₃, k_t shows the same trend as dielectric constant ε_r.Additionally, the electromechanical coupling factor k_t is obtained the relatively high value under the condition of the low poling field E_P owing to the reduced coercive field.更多还原