壓(ya)(ya)電(dian)(dian)效應(ying)(ying)的(de)原理是(shi)，如果對壓(ya)(ya)電(dian)(dian)材料施加壓(ya)(ya)力(li)(li)，它(ta)便(bian)會(hui)產生(sheng)電(dian)(dian)位(wei)差（稱(cheng)之(zhi)為正壓(ya)(ya)電(dian)(dian)效應(ying)(ying)），反之(zhi)施加電(dian)(dian)壓(ya)(ya)，則產生(sheng)機械應(ying)(ying)力(li)(li)（稱(cheng)為逆壓(ya)(ya)電(dian)(dian)效應(ying)(ying)）。也(ye)就(jiu)是(shi)說，壓(ya)(ya)電(dian)(dian)陶瓷具有(you)機械能(neng)與電(dian)(dian)能(neng)之(zhi)間的(de)轉換和逆轉換的(de)功能(neng)，這(zhe)種相互(hu)對應(ying)(ying)的(de)關系非常有(you)意思。
正壓電效應
當壓電(dian)(dian)(dian)(dian)(dian)材(cai)料(liao)(liao)受到(dao)某(mou)個固定方(fang)向外(wai)力(li)(li)(li)的作用(yong)時，內(nei)部就產(chan)生(sheng)(sheng)電(dian)(dian)(dian)(dian)(dian)極(ji)化(hua)現象，同時在某(mou)兩個表面上產(chan)生(sheng)(sheng)符(fu)號相(xiang)反的電(dian)(dian)(dian)(dian)(dian)荷；當外(wai)力(li)(li)(li)撤去后，材(cai)料(liao)(liao)又(you)恢(hui)復到(dao)不(bu)帶電(dian)(dian)(dian)(dian)(dian)的狀態；當外(wai)力(li)(li)(li)作用(yong)方(fang)向改變時，電(dian)(dian)(dian)(dian)(dian)荷的極(ji)性也隨(sui)之改變；材(cai)料(liao)(liao)受力(li)(li)(li)所產(chan)生(sheng)(sheng)的電(dian)(dian)(dian)(dian)(dian)荷量(liang)與外(wai)力(li)(li)(li)的大(da)小成(cheng)正比。這(zhe)種現象稱為(wei)正壓電(dian)(dian)(dian)(dian)(dian)效(xiao)應。壓電(dian)(dian)(dian)(dian)(dian)式(shi)傳感器大(da)多是利用(yong)正壓電(dian)(dian)(dian)(dian)(dian)效(xiao)應制成(cheng)的。
逆壓電效應
當對(dui)壓電(dian)(dian)材料施加電(dian)(dian)場時，材料的某(mou)些方向會出現機械形變的現象(xiang)，并(bing)且其形變量與外電(dian)(dian)場強度(du)成正比，這種現象(xiang)稱為(wei)逆壓電(dian)(dian)效應。用逆壓電(dian)(dian)效應制造的設備(bei)可(ke)用于超(chao)聲工程(cheng)和微運動領(ling)域。
壓電材料外部施加力F的產出計算
外部施加力下壓電材料產生的電荷Q或者電壓V就是正壓電效應的應用。通用常數比例變化（如壓電常數d33和Cd大小的變化）施加全部外部作用下，壓電陶瓷會對應產生電荷量Q。
Q=Cd×V=F×d33
此時(shi)輸出(chu)電壓V可由壓電材料元件(jian)的壓電常數g33、厚度t、截面積A的關系表達出(chu)來(lai)，具體見(jian)下公式：
V=F×d33/Cd=F×g33×t/A
舉(ju)例：壓(ya)(ya)電陶瓷(ci)截面(mian)積A=10×10mm2，厚度t=1mm，g33=26.5×10-3vm/N。當力F=10N時，得到輸出電壓(ya)(ya)V=2.65V。
壓電材料外部施加電壓V的產出計算
外部施加電壓壓電材料產生形變就是逆壓電效應的應用。在應用實例中，壓電材料可以在直流或低頻交流電下運行。此時，無負荷的電位移U和施加電壓V有下列關系：
U=V×d33
V：施加電壓
d33：壓電常數
舉例：壓電(dian)陶瓷d33=635×10-12m/V，施加電(dian)壓150V，位移(yi)U=95.25nm
（來(lai)源：網絡，版權歸原(yuan)作(zuo)者）
