Lead‐free Ba0.7Ca0.3Ti1−xSnxO3 (x=0.00, 0.025, 0.050, 0.075, and 0.1, abbreviated as BCST) electroceramic system was prepared by the solid‐state reaction method and its ferroelectric, piezoelectric, and electrostrictive properties were investigated. X‐ray diffraction shows that the compositions with x≤0.05 exhibit a tetragonal crystal structure having P4mm symmetry; while the compositions x=0.075 and 0.1 exhibit a mixed P4mm+Amm2 phase coexistence of tetragonal and orthorhombic and P4mm+Pmtrue3false¯m pseudo‐cubic lattice symmetries, respectively, at room temperature. The dense microstructure having relative density ~90%‐92% and average grain size in the range ~2.36 μm to 8.56 μm was observed for BCST ceramics. Temperature‐dependent dielectric measurements support the presence of phase coexistence and show the decrease in Curie temperature (TC) with Sn4+ substitution. The dielectric loss (tan δ) values in the temperature range (−100°C to 150°C) was observed to be <4%, for all BCST ceramics. The BCST compositions exhibit typical polarization‐electric field (P‐E) hysteresis and electric field induced strain (S‐E) butterfly loop, which confirms the ferroelectric and piezoelectric character. The compositions x=0.025, 0.05 and 0.075 show the peaking behavior of displacement current density (trueJ→) to an applied electric field (trueE→) (J‐E) which implies the saturation state of polarization. The maximum electrostrictive coefficient (Q33) value of 0.0667 m4/C2 was observed for x=0.075 and it is higher than some of the significant lead‐based electrostrictive materials. The compositions x=0.05 and 0.075 exhibit the notable electrostrictive properties that may be useful for piezoelectric Ac device applications. The observed results are discussed and correlated with the structure‐property‐composition.

Dense microstructure BaTiO₃ (BT) ceramic with c/a ~1.0144 and average grain size ~7.8 μm is developed by achieving the ferroelectric parameters Psat. = 24.13 μC/cm 2 and Pr = 10.42 μC/cm 2 with lower coercive field of Ec = 2.047 kV/cm. For BT ceramic, the "sprout" shape nature is observed for strain-electric field measurements with remnant strain ~ 0.212%, converse piezoelectric constant ~376.35 pm/V and electrostrictive coefficient Q 33~ 0.03493 m 4 /C 2. To tune the piezoelectric properties of BT ceramic, the substitutions of Ca 2+ and Sn 4+ , Zr 4+ are done for Ba 2+ and Ti 4+ sites respectively. The Ba 0.7 Ca 0.3 Ti 1-x Sn x O 3 (x = 0.00, 0.025, 0.050, 0.075, and 0.1, BCST) system was studied with ferroelectric, piezoelectric and electrostrictive properties. The electrostrictive coefficient (Q 33) ~ 0.0667 m 4 /C 2 was observed for x = 0.075 and it is higher than the lead-based electrostrictive materials. Another (1-X) Ba 0.95 Ca 0.05 Ti 0.92 Sn 0.08 O 3 (BCST)-(X) Ba 0.95 Ca 0.05 Ti 0.92 Zr 0.08 O 3 (BCZT), ceramics (x = 0.00, 0.25, 0.50, 0.75, and 1) is studied. The BCST-BCZT ceramic system shows the increase of polymorphic phase transition temperatures toward the room temperature by Ca 2+ , Sn 4+ and Zr 4+ substitution. For BCST-BCZT system the composition x = 0.75 exhibits the d 33 , and Q 33 values of 310 pC/N, 385 pm/V and 0.089 m 4 /C 2 respectively which is greater than BT ceramics.

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