Manganese-modified BiScO3–PbTiO3 piezoelectric ceramic for high-temperature shear mode sensor

The bismuth-based perovskite solid solution (100−x)BiScO3−xPbTiO3 (BSPT) was investigated for use at temperatures up to 400°C and above. The high-temperature resistivity, together with dielectric and piezoelectric behaviors of the shear mode for manganese-modified BSPT ceramics near the morphotropic phase boundary composition were studied. The resistivity and time constant were found to be 3×107Ωcm and 0.08s, respectively, at 450°C for modified BSPT66. The dielectric constant Κ11T and dielectric loss were found to be 1112 and 1%, respectively, at room temperature, showing a Curie temperature at 468°C. The electromechanical coupling factor k15 was calculated to be 61%, staying nearly constant up to 440°C, expanding the temperature usage range significantly. The properties indicate that the modified BSPT66 material is a promising candidate for high-temperature shear sensor applications.