History and recent progress in ferroelectrets produced in Brazil  

作　　者：Ruy Alberto Pisani Altafim Ruy Alberto Corrêa Altafim 

机构地区：[1]Computer Systems Department,Informatics Center,Federal University of Paraíba João Pessoa,PB,Brazil [2]Electrical and Computer Department,University of São Paulo,São Carlos,SP,Brazil

出　　处：《Journal of Advanced Dielectrics》2023年第4期27-34,共8页先进电介质学报（英文）

摘　　要：More than 30 years ago,a group of researchers in Tampere-Finland developed a thin foamed polymeric material for capacitive sensors.Such soft-voided films exhibited electrical charging characteristics,forming a powerful combination,which resulted in a smart-material with ferroelectric properties.The discovery of the electro-thermo mechanical film(ETMF)has sparked the curiosity of the electret community,leading to the development of several studies.At that time,ETMF became known as cellular electrets and,later,as ferroelectrets or piezoelectrets regarding their electromechanical properties.This paper provides a timeline review of the research on ferroelectrets produced in Brazil,between the years 1990 and 2020,towards demonstrating how the interest in the electret electrical charging mechanism has resulted in the use of ferroelectrets with well-controlled cavities for ultrasound applications.

关 键 词：Cellular electrets piezoelectrets FERROELECTRETS electromechanical films 

分 类 号：TB30[一般工业技术—材料科学与工程]