Process for the preparation of piezoelectric crystal elements
A process for the preparation of piezoelectric single crystal elements involving the steps of mechanically finishing of a single crystal element with cuttings such as zxt±45°, coating electrodes on a pair of Z surfaces, poling the single crystal in a direction along the <011> axis under a 500V/mm electric field.
1. A method for preparation of a single crystal element, comprising the steps of:
providing a single crystal element;
said single crystal element being a piezoelectric crystal element with a cutting direction along zxt±45°;
said single crystal element providing a PbZ y (Mg 1/2 Nb 2/3 ) 1-x-y Ti x O 3 ; wherein Y is defined as from 0 to 0.10, X is defined as 0.20 to 0.35, and Z is defined as at least one doped element selected from the group consisting of: Zr, Hf, Sn, In, Sc, Tm, Nb, Ta, Zn, Yb, Lu, Sb, Bi, Mn, Ga, Ce, Ni, W, Cu, Fe, K, Na, Li, and Ba;
mechanically finishing said single crystal with cuttings along zxt±45°;
coating electrodes on a pair of Z surfaces;
poling said single crystal element to a first poled state in the direction along <011> cubic axis under a 500V/mm electrical field at room temperature and forming a poled single crystal element; and
providing said poled single crystal element with an operable d 36 shear mode and having a d 36 value up to about 2600 pC/N at room temperature.
2. A method, according to claim 1 , further comprising the step of:
repoling said poled single crystal element in said first poled state to a second polled state.