Perovskite Relaxor Ferroelectric Modified BCZT-based Lead-free Piezoelectric Ceramics

Piezoelectric ceramic is a kind of information functional material,which can convert electrical energy and mechanical energy to each other.Currently,lead zirconate titanate(PZT)piezoelectric materials are mainly used in the market.However,the Pb₃O₄ in the ceramics of this system has strong biological toxicity,which can cause serious harm to the environment and human body.Therefore,it is imperative to develop alternatives to lead-based ceramics.In this context,(Ba_0.85Ca_0.15)(Ti_0.9Zr_0.1)O₃(BCZT)-based ceramics have excellent electrical properties and are a material that has the potential to replace lead-based ceramics.Therefore,in this paper,BCZT based ceramics as the research basis,through component introduction,precursor preparation and optimization of the preparation process and other means to improve the comprehensive electrical properties of BCZT based ceramics,to further promote the commercialization of lead-free ceramics.(1)Prepare(1-x)BCZT-x BLT ceramics by solid phase method and molten salt synthesis precursor method.The study found that the piezoelectric properties of(1-x)BCZT-x BLT ceramic prepared by solid phase method are better than that of molten salt synthesis precursor method.(1-x)BCZT-x BLT ceramics coexist in multiple phases.The introduction of BLT can promote the growth of BCZT-based ceramic grains.When the BLT content is x=0.2%,0.998BCZT-0.002BLT ceramic has the best comprehensive electrical properties.(2)Synthesis of(Bi_0.5Na_0.5)TiO₃(BNT)precursor modified BCZT-based ceramics by molten salt method.The study found that the BNT precursor modified BCZT-based ceramics synthesized at 820? has the best overall performance.0.998BCZT-0.002BNT ceramics have multi-phase coexistence.The introduction of BNT precursor can promote the growth of 0.998BCZT-0.002BNT ceramic grains.(3)Synthesis of(Bi_0.5K_0.5)TiO₃(BKT)precursor modified BCZT-based ceramics by molten salt method.The study found that the BCZT-based ceramics modified by the BKT precursor synthesized at 830? has the best performance.The ceramic samples sintered at 1420? has good electrical properties.0.996BCZT-0.004BKT ceramics have multi-phase coexistence.As the sintering temperature increases,the grains of0.996BCZT-0.004BKT ceramics grow significantly.(4)Synthesis of BNT precursor modified BCZT-based ceramics by hydrothermal method.When BNT is synthesized at 220?,0.998BCZT-0.002BNT ceramic has better electrical properties.0.998BCZT-0.002BNT ceramics have multi-phase coexistence.The crystal grains of 0.998BCZT-0.002BNT ceramic prepared by hydrothermal method are obviously enlarged.