The present invention relates to a method for identifying a solid solution ceramic material of a plurality of perovskite compounds which exhibits an electric field induced strain derived from a reversible phase transition, as well as a method for making such ceramic materials and ceramic materials obtainable therefrom. In particular, the present invention is directed to a method of identifying a solid solution ceramic material of at least three perovskite compounds which exhibits an electric field induced strain derived from a reversible phase transition; said method comprising the steps of: i) determining a molar ratio of at least one tetragonal perovskite compound to at least one non-tetragonal perovskite compound which, when combined to form a solid solution, provides a ceramic material comprising a major portion of a tetragonal phase having an axial ratio c/a of greater than 1.005 to 1.04; and ii) determining a molar ratio of at least one additional non-tetragonal perovskite compound to the combination of perovskite compounds from step i) at the determined molar ratio which, when combined to form a solid solution, provides a ceramic material comprising a major portion of a pseudo-cubic phase having an axial ratio c/a of from 0.995 to 1.005 and/or a rhombohedral angle of 90±0.5 degrees.

The present invention relates to a method for identifying a solid solution ceramic material of a plurality of perovskite compounds which exhibits an electric field induced strain derived from a reversible phase transition, as well as a method for making such ceramic materials and ceramic materials obtainable therefrom. In particular, the present invention is directed to a method of identifying a solid solution ceramic material of at least three perovskite compounds which exhibits an electric field induced strain derived from a reversible phase transition; said method comprising the steps of: i) determining a molar ratio of at least one tetragonal perovskite compound to at least one non-tetragonal perovskite compound which, when combined to form a solid solution, provides a ceramic material comprising a major portion of a tetragonal phase having an axial ratio c/a of greater than 1.005 to 1.04; and ii) determining a molar ratio of at least one additional non-tetragonal perovskite compound to the combination of perovskite compounds from step i) at the determined molar ratio which, when combined to form a solid solution, provides a ceramic material comprising a major portion of a pseudo-cubic phase having an axial ratio c/a of from 0.995 to 1.005 and/or a rhombohedral angle of 90±0.5 degrees.

The present invention relates to a bismuth-based solid solution ceramic material, as well as a process for preparing the ceramic material and uses thereof, particularly in an actuator component employed, for example, in a droplet deposition apparatus. In particular, the present invention relates to a ceramic material having a general chemical formula (I): (I): x(Bi.sub.0.5Na.sub.0.5)TiO.sub.3-y(Bi.sub.0.5K.sub.0.5)TiO.sub.3-z.sub.1SrHfO.sub.3-z.sub.2SrZrO.sub.3, wherein x+y+Z.sub.1+Z.sub.2=1; y, (z.sub.1+z.sub.2)≠0; x≥0. In embodiments, the present invention also relates to a ceramic material having a general chemical formula (II): x(Bi0.5Na0.5)TiO3-y(Bi0.5K0.5)TiO3-y(Bi0.5K0.5)TiO3-ZiSrHfO3-z2SrZrO3, wherein x+y+z−i+z2=1; x, y, fa+z2)≠0; as well as a ceramic material of general formula (III): y(Bi.sub.0.5K.sub.0.5)TiO.sub.3-z.sub.1SrHfO.sub.3-z.sub.2SrZrO.sub.3, wherein y+z.sub.1,+z.sub.2=1; y, (z.sub.1+z.sub.2)≠0.

The present invention relates to a bismuth-based solid solution ceramic material, as well as a process for preparing the ceramic material and uses thereof, particularly in an actuator component employed, for example, in a droplet deposition apparatus. In particular, the present invention relates to a ceramic material having a general chemical formula (I): (I): x(Bi.sub.0.5Na.sub.0.5)TiO.sub.3-y(Bi.sub.0.5K.sub.0.5)TiO.sub.3-z.sub.1SrHfO.sub.3-z.sub.2SrZrO.sub.3, wherein x+y+Z.sub.1+Z.sub.2=1; y, (z.sub.1+z.sub.2)≠0; x≥0. In embodiments, the present invention also relates to a ceramic material having a general chemical formula (II): x(Bi0.5Na0.5)TiO3-y(Bi0.5K0.5)TiO3-y(Bi0.5K0.5)TiO3-ZiSrHfO3-z2SrZrO3, wherein x+y+z−i+z2=1; x, y, fa+z2)≠0; as well as a ceramic material of general formula (III): y(Bi.sub.0.5K.sub.0.5)TiO.sub.3-z.sub.1SrHfO.sub.3-z.sub.2SrZrO.sub.3, wherein y+z.sub.1,+z.sub.2=1; y, (z.sub.1+z.sub.2)≠0.

A manufacturing method of a dielectric ceramic composition includes attaching a reactive functional group to a surface of a base material powder particle of a perovskite structure.

An electroactive ceramic may be incorporated into a transparent optical element and may characterized by an average grain size of less than 200 nm, a relative density of at least 99%, and a transmissivity within the visible spectrum of at least 50%, while maintaining a d.sub.33 value of at least 20 pC/N. Optical properties of the electroactive ceramic, including transmissivity, haze, and clarity may be substantially unchanged during actuation of the optical element and the attendant application of a voltage to a layer of the electroactive ceramic.

An electroactive ceramic may be incorporated into a transparent optical element and may characterized by an average grain size of less than 200 nm, a relative density of at least 99%, and a transmissivity within the visible spectrum of at least 50%, while maintaining a d.sub.33 value of at least 20 pC/N. Optical properties of the electroactive ceramic, including transmissivity, haze, and clarity may be substantially unchanged during actuation of the optical element and the attendant application of a voltage to a layer of the electroactive ceramic.

An electroactive ceramic may be incorporated into a transparent optical element between transparent electrodes and may characterized by a preferred crystallographic orientation. The preferred crystallographic orientation may be aligned along a polar axis of the electroactive ceramic and substantially parallel to each of the electrodes. Optical properties of the optical element, including transmissivity, haze, and clarity may be substantially unchanged during actuation thereof and the attendant application of a voltage to the electroactive ceramic.

A piezoelectric composition comprises a plurality of crystal particles, wherein the piezoelectric composition includes bismuth, iron, barium, titanium, and oxygen; the crystal particles include a core and a shell covering the core; the average value of the contents of bismuth in the cores is expressed as C.sub.CORE % by mass, the average value of the contents of bismuth in the shells is expressed as C.sub.SHELL % by mass, and the C.sub.CORE is lower than the C.sub.SHELL; and the number of all the particles comprised in the piezoelectric composition is expressed as N, the number of the crystal particles including the core and the shell is expressed as n, and n/N is 0.10 to 1.00.

A piezoelectric composition comprises a plurality of crystal particles, wherein the piezoelectric composition includes bismuth, iron, barium, titanium, and oxygen; the crystal particles include a core and a shell covering the core; the average value of the contents of bismuth in the cores is expressed as C.sub.CORE % by mass, the average value of the contents of bismuth in the shells is expressed as C.sub.SHELL % by mass, and the C.sub.CORE is lower than the C.sub.SHELL; and the number of all the particles comprised in the piezoelectric composition is expressed as N, the number of the crystal particles including the core and the shell is expressed as n, and n/N is 0.10 to 1.00.