電加(jia)熱(re)(re)器(qi)是指利用電能達到加(jia)熱(re)(re)效果的(de)電器(qi)，按加(jia)熱(re)(re)方式(shi)的(de)種(zhong)類(lei)(lei)來區分(fen)，大(da)可分(fen)為(wei)三類(lei)(lei):

1.電磁加熱(re)(Electromagnetic heating)

電(dian)(dian)(dian)磁(ci)加熱是通過(guo)電(dian)(dian)(dian)子線路(lu)板組成部(bu)(bu)(bu)分(fen)產生(sheng)交變磁(ci)場(chang)、當(dang)用(yong)含鐵質容(rong)(rong)器(qi)(qi)(qi)(qi)放置上(shang)面時，容(rong)(rong)器(qi)(qi)(qi)(qi)表面具即(ji)切(qie)割交變磁(ci)力線而(er)在容(rong)(rong)器(qi)(qi)(qi)(qi)底(di)部(bu)(bu)(bu)金屬部(bu)(bu)(bu)分(fen)產生(sheng)交變的電(dian)(dian)(dian)流(即(ji)渦流)，渦流使(shi)容(rong)(rong)器(qi)(qi)(qi)(qi)底(di)部(bu)(bu)(bu)的鐵原子高(gao)速無規則運動，原子互相碰撞、摩擦而(er)產生(sheng)熱能。從而(er)起到(dao)(dao)加熱物品的效果 。因為是鐵制容(rong)(rong)器(qi)(qi)(qi)(qi)自身(shen)發熱，所(suo)有熱轉(zhuan)化率特別高(gao)，最高(gao)可(ke)達到(dao)(dao)95%。電(dian)(dian)(dian)磁(ci)爐，電(dian)(dian)(dian)磁(ci)灶(zao)都是采用(yong)的電(dian)(dian)(dian)磁(ci)加熱技術。

2.紅(hong)外線加熱

紅外(wai)線(xian)(xian)的(de)傳熱(re)形(xing)式(shi)是輻射(she)(she)傳熱(re)，由電磁波(bo)傳遞(di)能量。在遠(yuan)(yuan)紅外(wai)線(xian)(xian)照射(she)(she)到(dao)被加熱(re)的(de)物(wu)體(ti)(ti)時(shi)，一部(bu)(bu)分射(she)(she)線(xian)(xian)被反射(she)(she)回(hui)來，一部(bu)(bu)分被穿透過去。當發射(she)(she)的(de)遠(yuan)(yuan)紅外(wai)線(xian)(xian)波(bo)長和(he)被加熱(re)物(wu)體(ti)(ti)的(de)吸(xi)收波(bo)長一致(zhi)時(shi)，被加熱(re)的(de)物(wu)體(ti)(ti)吸(xi)收遠(yuan)(yuan)紅外(wai)線(xian)(xian)，這時(shi)，物(wu)體(ti)(ti)內部(bu)(bu)分子(zi)和(he)原子(zi)發生"共(gong)振"--產生強烈的(de)振動(dong)、旋轉(zhuan)，而振動(dong)和(he)旋轉(zhuan)使物(wu)體(ti)(ti)溫度升高，達到(dao)了加熱(re)的(de)目的(de) 。

3.電阻加熱(Resistance heating)

利用電(dian)(dian)流通過電(dian)(dian)熱(re)(re)體放出(chu)熱(re)(re)量來加(jia)熱(re)(re)坯料(liao)的(de)(de)加(jia)熱(re)(re)方法。 常見的(de)(de)電(dian)(dian)阻絲加(jia)熱(re)(re)，陶瓷加(jia)熱(re)(re)器(qi)，以及(ji)電(dian)(dian)阻圈加(jia)熱(re)(re)，石英管(guan)加(jia)熱(re)(re)，原理上都屬于電(dian)(dian)阻式加(jia)熱(re)(re)。