Textured BaTiO_(3)(BT)-based lead-free ceramics have gained significant attention due to their high piezoelectric coefficient(d)and very large field induced strain(S).However,costly nano-size raw materials,excessively...Textured BaTiO_(3)(BT)-based lead-free ceramics have gained significant attention due to their high piezoelectric coefficient(d)and very large field induced strain(S).However,costly nano-size raw materials,excessively high sintering temperature and low Curie temperature(T_(c))hinder their device applications.In this work,highly[001]_(c)-oriented(Ba_(0.95)Ca_(0.05))(Zr_(0.04)Ti_(0.96))O_(3) ceramics with x mol%CuO(x=0.25,0.5,1.0,2.5)denoted as BCZT-x were synthesized by templated grain growth using micro-sized raw powders.The introduction of CuO sintering agent lowered the sintering temperature by 125℃ to 1450℃,and the BCZT-1.0 achieved a high texture degree of∼99%.In addition,the CuO-based liquid phases eliminated boundaries between BT templates and BCZT matrix powders.Such liquid-phase sintering reduced sintering stresses,decreased the average grain size of BCZT-1.0 from 16μm down to 13μm,and increased the dielectric dispersion coefficientγto 1.63.The almost smoothed out T_(O-T) anomaly in the temperature dependence of dielectric permittivity and comparably high T_(c)(>102℃)lead to better temperature stability.The narrower grain orientation distribution with full width at half maximum(FWHM)of∼5.9°and smaller domains with the size of 0.1–0.5μm in width and 3–8μm in length were obtained,a high field induced maximum strain S_(max) of 0.38%and low H_(s) of 5.2%have been achieved in BCZT-1.0 textured ceramics together with a high and homogeneous piezoelectric stress coefficient d_(33)∼780 pC/N and very large d_(33)∗∼2950 pm/V.展开更多
基金This work was supported by the Postdoctoral Science Foundation(Nos.BX20490103,2020M681089,LBH-Z19065 and LBHZ13109)the National Natural Science Foundation of China(No.52002093).
文摘Textured BaTiO_(3)(BT)-based lead-free ceramics have gained significant attention due to their high piezoelectric coefficient(d)and very large field induced strain(S).However,costly nano-size raw materials,excessively high sintering temperature and low Curie temperature(T_(c))hinder their device applications.In this work,highly[001]_(c)-oriented(Ba_(0.95)Ca_(0.05))(Zr_(0.04)Ti_(0.96))O_(3) ceramics with x mol%CuO(x=0.25,0.5,1.0,2.5)denoted as BCZT-x were synthesized by templated grain growth using micro-sized raw powders.The introduction of CuO sintering agent lowered the sintering temperature by 125℃ to 1450℃,and the BCZT-1.0 achieved a high texture degree of∼99%.In addition,the CuO-based liquid phases eliminated boundaries between BT templates and BCZT matrix powders.Such liquid-phase sintering reduced sintering stresses,decreased the average grain size of BCZT-1.0 from 16μm down to 13μm,and increased the dielectric dispersion coefficientγto 1.63.The almost smoothed out T_(O-T) anomaly in the temperature dependence of dielectric permittivity and comparably high T_(c)(>102℃)lead to better temperature stability.The narrower grain orientation distribution with full width at half maximum(FWHM)of∼5.9°and smaller domains with the size of 0.1–0.5μm in width and 3–8μm in length were obtained,a high field induced maximum strain S_(max) of 0.38%and low H_(s) of 5.2%have been achieved in BCZT-1.0 textured ceramics together with a high and homogeneous piezoelectric stress coefficient d_(33)∼780 pC/N and very large d_(33)∗∼2950 pm/V.
