Patent · US Expired

Heat cycle treatment for improving the performance of piezoelectric ceramics

US5004555A · kind A · utility

5Cited by
5References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 31, 1989
Grant dateApr 2, 1991
Priority date
Expiry dateOct 31, 2009

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10N30/8554
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A process for improving the electromechanical coupling factor (Kp) of a polarized piezoelectric ceramics by thermal cycle treatment. The process comprises the steps of: PA0 (a) keeping the polarized piezoelectric ceramics at a temperature of from 50.degree. to 130.degree. C. for from 10 to 60 minutes; PA0 (b) cooling the polarized piezoelectric ceramics to room temperature rapidly; PA0 (a) repeating steps (a) and (b) until the electromechanical coupling factor of the polarized piezoelectric ceramics saturates. The process of the present invention is effective in elevating the electromechanical coupling factor (Kp) of a polarized piezoelectric ceramics by an degree of from 3 to 8 percent. The useful life of the polarized piezoelectric ceramics is therefore elongated.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.