{"id":59267,"date":"2023-04-22T00:00:37","date_gmt":"2023-04-22T05:00:37","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/how-to-make-piezoelectric-ceramic\/"},"modified":"2025-01-27T06:11:17","modified_gmt":"2025-01-27T11:11:17","slug":"how-to-make-piezoelectric-ceramic","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/cs\/how-to-make-piezoelectric-ceramic\/","title":{"rendered":"V\u00fdroba piezoelektrick\u00e9 keramiky: Komplexn\u00ed pr\u016fvodce"},"content":{"rendered":"<p>Piezoelektrick\u00e1 keramika je materi\u00e1l s unik\u00e1tn\u00edmi vlastnostmi, schopn\u00fd p\u0159em\u011b\u0148ovat mechanickou energii na energii elektrickou a naopak.  Jeho v\u00fdroba je komplexn\u00ed proces zahrnuj\u00edc\u00ed n\u011bkolik kl\u00ed\u010dov\u00fdch krok\u016f, od p\u0159\u00edpravy surovin a\u017e po fin\u00e1ln\u00ed tepeln\u00e9 zpracov\u00e1n\u00ed.  Pochopen\u00ed t\u011bchto krok\u016f je nezbytn\u00e9 pro v\u00fdrobu vysoce kvalitn\u00edho piezoelektrick\u00e9ho materi\u00e1lu s po\u017eadovan\u00fdmi vlastnostmi.<\/p>\n<h3>P\u0159\u00edprava surovin<\/h3>\n<p>V\u00fdroba piezoelektrick\u00e9 keramiky za\u010d\u00edn\u00e1 pe\u010dlivou p\u0159\u00edpravou surovin.  Nejb\u011b\u017en\u011bj\u0161\u00edmi slo\u017ekami jsou titanit barnat\u00fd (BaTiO\u2083) a zirkonit olovnat\u00fd (PbZrO\u2083), kter\u00e9 se m\u00eds\u00ed v p\u0159esn\u011b definovan\u00fdch pom\u011brech v z\u00e1vislosti na po\u017eadovan\u00fdch piezoelektrick\u00fdch vlastnostech.  Dal\u0161\u00ed slo\u017eky, jako nap\u0159\u00edklad niob\u00e1t draseln\u00fd (KNbO\u2083) nebo tantal\u00e1t lithn\u00fd (LiTaO\u2083), se p\u0159id\u00e1vaj\u00ed pro optimalizaci vlastnost\u00ed, jako je piezoelektrick\u00fd koeficient, dielektrick\u00e1 konstanta a Curieova teplota.  Suroviny jsou nejprve d\u016fkladn\u011b prom\u00edch\u00e1ny a n\u00e1sledn\u011b rozemlety na jemn\u00fd pr\u00e1\u0161ek, typicky s velikost\u00ed \u010d\u00e1stic pod 1 \u03bcm, aby se dos\u00e1hlo homogenn\u00ed sm\u011bsi.<\/p>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Slo\u017eka<\/th>\n<th>Chemick\u00fd vzorec<\/th>\n<th>Funkce<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Titanit barnat\u00fd<\/td>\n<td>BaTiO\u2083<\/td>\n<td>Z\u00e1kladn\u00ed piezoelektrick\u00e1 slo\u017eka<\/td>\n<\/tr>\n<tr>\n<td>Zirkonit olovnat\u00fd<\/td>\n<td>PbZrO\u2083<\/td>\n<td>Z\u00e1kladn\u00ed piezoelektrick\u00e1 slo\u017eka<\/td>\n<\/tr>\n<tr>\n<td>Niob\u00e1t draseln\u00fd<\/td>\n<td>KNbO\u2083<\/td>\n<td>Modifikace piezoelektrick\u00fdch vlastnost\u00ed<\/td>\n<\/tr>\n<tr>\n<td>Tantal\u00e1t lithn\u00fd<\/td>\n<td>LiTaO\u2083<\/td>\n<td>Modifikace piezoelektrick\u00fdch vlastnost\u00ed<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>Kalcinace a mlet\u00ed<\/h3>\n<p>Sm\u011bs rozemlet\u00fdch surovin je n\u00e1sledn\u011b kalcinov\u00e1na p\u0159i vysok\u00fdch teplot\u00e1ch (obvykle 800-1200 \u00b0C) po dobu n\u011bkolika hodin.  Kalcinace vede k tvorb\u011b perovskitov\u00e9 krystalov\u00e9 struktury, kter\u00e1 je nezbytn\u00e1 pro piezoelektrick\u00e9 vlastnosti.  Po kalcinaci se v\u00fdsledn\u00fd materi\u00e1l znovu rozmele na jemn\u00fd pr\u00e1\u0161ek, aby se odstranily agreg\u00e1ty a zlep\u0161ila se homogenita.  Kvalita mlet\u00ed je kl\u00ed\u010dov\u00e1 pro dosa\u017een\u00ed po\u017eadovan\u00fdch vlastnost\u00ed fin\u00e1ln\u00edho produktu.<\/p>\n<h3>Lisov\u00e1n\u00ed a sp\u00e9k\u00e1n\u00ed<\/h3>\n<p>Jemn\u00fd pr\u00e1\u0161ek se lisuje pod vysok\u00fdm tlakem do po\u017eadovan\u00e9ho tvaru (desti\u010dky, trubi\u010dky, apod.).  Tlak se vol\u00ed podle tvaru a velikosti v\u00fdrobku.  Po lisov\u00e1n\u00ed n\u00e1sleduje sp\u00e9k\u00e1n\u00ed, co\u017e je tepeln\u00e1 \u00faprava p\u0159i je\u0161t\u011b vy\u0161\u0161\u00edch teplot\u00e1ch (obvykle 1200-1400 \u00b0C) po dobu n\u011bkolika hodin.  B\u011bhem sp\u00e9k\u00e1n\u00ed doch\u00e1z\u00ed k dif\u00fazi a rekrystalizaci, \u010d\u00edm\u017e se vytv\u00e1\u0159\u00ed pevn\u00fd a hust\u00fd keramick\u00fd materi\u00e1l.  D\u016fkladn\u00e9 \u0159\u00edzen\u00ed procesu sp\u00e9k\u00e1n\u00ed je kl\u00ed\u010dov\u00e9 pro dosa\u017een\u00ed po\u017eadovan\u00e9 hustoty a mikrostruktury.<\/p>\n<h3>Polarizace<\/h3>\n<p>Sp\u00e9k\u00e1n\u00edm vznikl\u00fd keramick\u00fd materi\u00e1l je elektricky neutr\u00e1ln\u00ed.  Aby se z\u00edskaly piezoelektrick\u00e9 vlastnosti, je nutn\u00e9 prov\u00e9st polarizaci.  To se d\u011bl\u00e1 aplikac\u00ed siln\u00e9ho elektrick\u00e9ho pole (n\u011bkolik kV\/mm) p\u0159i teplot\u011b t\u011bsn\u011b pod Curieovou teplotou dan\u00e9ho materi\u00e1lu.  Polarizace uspo\u0159\u00e1d\u00e1 elektrick\u00e9 dip\u00f3ly v keramick\u00e9 struktu\u0159e, \u010d\u00edm\u017e se vyvol\u00e1 piezoelektrick\u00fd efekt.  Proces polarizace je ireverzibiln\u00ed a je d\u016fle\u017eit\u00fd pro ur\u010den\u00ed sm\u011bru piezoelektrick\u00e9 odezvy.<\/p>\n<h3>Elektrodov\u00e9 povlakov\u00e1n\u00ed a fin\u00e1ln\u00ed zpracov\u00e1n\u00ed<\/h3>\n<p>Po polarizaci se na povrch piezoelektrick\u00e9 keramiky nanese vodiv\u00e1 vrstva, obvykle elektrody z kov\u016f, jako je st\u0159\u00edbro nebo zlato.  Elektrody umo\u017e\u0148uj\u00ed p\u0159ipojen\u00ed k elektrick\u00e9mu obvodu a vyu\u017e\u00edv\u00e1n\u00ed piezoelektrick\u00e9ho efektu.  V z\u00e1vislosti na aplikaci m\u016f\u017ee n\u00e1sledovat fin\u00e1ln\u00ed zpracov\u00e1n\u00ed, jako je brou\u0161en\u00ed, le\u0161t\u011bn\u00ed a metalizace.<\/p>\n<p>Z\u00e1v\u011brem lze \u0159\u00edci, \u017ee v\u00fdroba piezoelektrick\u00e9 keramiky je n\u00e1ro\u010dn\u00fd technologick\u00fd proces, kter\u00fd vy\u017eaduje precizn\u00ed \u0159\u00edzen\u00ed v\u0161ech krok\u016f, od p\u0159\u00edpravy surovin a\u017e po fin\u00e1ln\u00ed \u00fapravy.  Kvalita fin\u00e1ln\u00edho produktu z\u00e1vis\u00ed na mnoha faktorech, v\u010detn\u011b kvality surovin, homogenity sm\u011bsi, parametr\u016f kalcinace, lisov\u00e1n\u00ed, sp\u00e9k\u00e1n\u00ed a polarizace.  Dosa\u017een\u00ed optimalizovan\u00fdch vlastnost\u00ed piezoelektrick\u00e9 keramiky vy\u017eaduje d\u016fkladn\u00e9 pochopen\u00ed t\u011bchto proces\u016f a jejich vz\u00e1jemn\u00fdch souvislost\u00ed.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Piezoelektrick\u00e1 keramika je materi\u00e1l s unik\u00e1tn\u00edmi vlastnostmi, schopn\u00fd p\u0159em\u011b\u0148ovat mechanickou energii na energii elektrickou a naopak. Jeho v\u00fdroba je komplexn\u00ed proces zahrnuj\u00edc\u00ed n\u011bkolik kl\u00ed\u010dov\u00fdch krok\u016f, od p\u0159\u00edpravy surovin a\u017e po fin\u00e1ln\u00ed tepeln\u00e9 zpracov\u00e1n\u00ed. Pochopen\u00ed t\u011bchto krok\u016f je nezbytn\u00e9 pro v\u00fdrobu vysoce kvalitn\u00edho piezoelektrick\u00e9ho materi\u00e1lu s po\u017eadovan\u00fdmi vlastnostmi. P\u0159\u00edprava surovin V\u00fdroba piezoelektrick\u00e9 keramiky za\u010d\u00edn\u00e1 pe\u010dlivou p\u0159\u00edpravou<\/p>\n","protected":false},"author":1,"featured_media":23772,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6415],"tags":[],"class_list":["post-59267","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","prodpage-classic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/59267","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/comments?post=59267"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/59267\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media\/23772"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media?parent=59267"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/categories?post=59267"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/tags?post=59267"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}