Enhanced breakdown strength and improved ferroelectric properties in lead-containing relaxor ferroelectric ceramics with addition of glass

Relaxor ferroelectrics (RFEs), which possess high maximum polarization (P _max), low remnant polarization (P _r) and coercive field (E _c), are good candidates for the applications in electrostrictive devices. Compared to lead-free RFEs, lead-containing RFEs possess higher P _max, due to the contribution by lead ions. However, relatively low breakdown strength (BDS) in lead-containing RFEs becomes a bottleneck for exploring the electrostrictive properties especially at higher electric field. In this work, we synthesized (1-x)[0.5573Pb(Mg_1/3Nb_2/3)O₃-0.4427PbTiO₃]-xBa(Zn_1/3Nb_2/3)O₃ [(1-x)PMNT-xBZN, x = 0.1725, 0.1925, 02125 and 0.2325] RFE ceramics with addition of Li₂O-B₂O₃-SiO₂ glass additives (2 wt%) and studied the BDS and dielectric/ferroelectric properties in detail. It was found that an enhancement of BDS from ∼120 kV cm^-1 for undoped samples to ∼160 kV cm^-1 for glass-doped samples. Higher P _max, lower P _r and lower E _c were simultaneously obtained in x = 0.1725, 0.1925 and 02125 compositions, suggesting improved ferroelectric properties. Purely electrostrictive strains with levels from 0.147% to 0.069% were obtained in glass-doped compositions when x increases from 0.1725 to 0.2325 at 30 °C, and more than 40% strain response were maintained when temperature is increased to 130 °C. This work proves the effectiveness of glass additives to enhance BDS and improve ferroelectric properties in lead-based (1-x)PMNT-xBZN RFE ceramics.