SAETT ATT PERMANENT POLARISERA PIETZOELEKTRISKT MATERIAL MED HJAELP AV ELEKTRISKA FAELT

摘要

1432879 Piezoelectric devices SIEMENS AG 16 July 1973 [17 July 1973] 33705/73 Heading H1E A process for polarizing a piezoelectric material comprises first polarizing the material in a D.C. field to a value above the desired polarization value and then depolarizing with an oppositely directed field until the desired level is reached. The depolarization takes place in steps with the polarization value being measured between consecutive steps and this process can be automated to stop when the desired level has been attained. The process can take place at room temperature but the polarization can take place at an elevated temperature.