{"id":63196,"date":"2022-07-20T08:55:24","date_gmt":"2022-07-20T13:55:24","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/piezo-ceramics-how-to-explain-thepyroelectric-effect\/"},"modified":"2025-01-27T06:14:54","modified_gmt":"2025-01-27T11:14:54","slug":"piezo-ceramics-how-to-explain-thepyroelectric-effect","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/cs\/piezo-ceramics-how-to-explain-thepyroelectric-effect\/","title":{"rendered":"Piezokeradika: Vysv\u011btlen\u00ed pyroelektrick\u00e9ho efektu"},"content":{"rendered":"

Piezoelektrick\u00fd jev je dob\u0159e zn\u00e1m\u00fd u piezoelektrick\u00fdch materi\u00e1l\u016f, ale m\u00e9n\u011b diskutovan\u00fd je pyroelektrick\u00fd efekt, kter\u00fd se u n\u011bkter\u00fdch z nich, v\u010detn\u011b piezo keramiky, tak\u00e9 projevuje. Pyroelekt\u0159ina je vlastnost n\u011bkter\u00fdch materi\u00e1l\u016f, kter\u00e9 generuj\u00ed elektrick\u00fd n\u00e1boj v reakci na zm\u011bnu teploty. Tento \u010dl\u00e1nek se zam\u011b\u0159\u00ed na vysv\u011btlen\u00ed pyroelektrick\u00e9ho efektu v kontextu piezo keramiky.<\/p>\n

Struktura piezoelektrick\u00e9ho a pyroelektrick\u00e9ho materi\u00e1lu<\/p>\n

Piezoelektrick\u00e9 materi\u00e1ly, a tedy i piezo keramika, jsou charakteristick\u00e9 svou schopnost\u00ed generovat elektrick\u00e9 nap\u011bt\u00ed p\u0159i mechanick\u00e9 deformaci a naopak se deformovat p\u0159i p\u016fsoben\u00ed elektrick\u00e9ho pole. Tato vlastnost je spojena s asymetri\u00ed krystalov\u00e9 struktury materi\u00e1lu. Pyroelektrick\u00fd efekt je speci\u00e1ln\u00edm p\u0159\u00edpadem piezoelektrick\u00e9ho efektu, kde se mechanick\u00e1 deformace zp\u016fsobuje teplotn\u00ed zm\u011bnou. V pyroelektrick\u00fdch materi\u00e1lech je spont\u00e1nn\u00ed elektrick\u00e1 polarizace, kter\u00e1 z\u00e1vis\u00ed na teplot\u011b. Zm\u011bna teploty vede ke zm\u011bn\u011b t\u00e9to polarizace, a t\u00edm k vzniku elektrick\u00e9ho n\u00e1boje na povrchu materi\u00e1lu. Je d\u016fle\u017eit\u00e9 si uv\u011bdomit, \u017ee v\u0161echny pyroelektrick\u00e9 materi\u00e1ly jsou piezoelektrick\u00e9, ale ne v\u0161echny piezoelektrick\u00e9 materi\u00e1ly jsou pyroelektrick\u00e9.<\/p>\n

Mechanismus pyroelektrick\u00e9ho efektu v piezo keramice<\/p>\n

Pyroelektrick\u00fd efekt v piezo keramice je zp\u016fsoben zm\u011bnou spont\u00e1nn\u00ed polarizace v d\u016fsledku teplotn\u00ed zm\u011bny. Spont\u00e1nn\u00ed polarizace je v\u00fdsledkem asymetrick\u00e9ho uspo\u0159\u00e1d\u00e1n\u00ed dip\u00f3l\u016f v krystalov\u00e9 m\u0159\u00ed\u017ece materi\u00e1lu. Zv\u00fd\u0161en\u00ed teploty vede k vibraci atom\u016f v krystalov\u00e9 m\u0159\u00ed\u017ece, co\u017e ovliv\u0148uje orientaci dip\u00f3l\u016f a sni\u017euje spont\u00e1nn\u00ed polarizaci. Tento posun dip\u00f3l\u016f generuje elektrick\u00fd n\u00e1boj na povrchu keramiky. Naopak sn\u00ed\u017een\u00ed teploty zvy\u0161uje spont\u00e1nn\u00ed polarizaci a generuje opa\u010dn\u011b polarizovan\u00fd n\u00e1boj. M\u00edra generovan\u00e9ho n\u00e1boje z\u00e1vis\u00ed na teplotn\u00edm koeficientu pyroelektrick\u00e9 konstanty materi\u00e1lu.<\/p>\n

Faktory ovliv\u0148uj\u00edc\u00ed pyroelektrick\u00fd efekt<\/p>\n

R\u016fzn\u00e9 faktory ovliv\u0148uj\u00ed velikost pyroelektrick\u00e9ho efektu v piezo keramice. Mezi nejd\u016fle\u017eit\u011bj\u0161\u00ed pat\u0159\u00ed:<\/p>\n\n\n\n\n\n\n\n\n\n
Faktor<\/th>\nVliv na pyroelektrick\u00fd efekt<\/th>\n<\/tr>\n<\/thead>\n
Typ keramiky<\/td>\nR\u016fzn\u00e9 typy piezo keramiky vykazuj\u00ed r\u016fznou pyroelektrickou odezvu.<\/td>\n<\/tr>\n
Teplotn\u00ed zm\u011bna<\/td>\n\u010c\u00edm v\u011bt\u0161\u00ed teplotn\u00ed zm\u011bna, t\u00edm v\u011bt\u0161\u00ed generovan\u00fd n\u00e1boj.<\/td>\n<\/tr>\n
Teplotn\u00ed gradient<\/td>\nNerovnom\u011brn\u00e9 zah\u0159\u00edv\u00e1n\u00ed m\u016f\u017ee v\u00e9st k nehomogenn\u00ed polarizaci.<\/td>\n<\/tr>\n
Orientace krystalov\u00e9 struktury<\/td>\nOrientace krystal\u016f v keramice ovliv\u0148uje velikost efektu.<\/td>\n<\/tr>\n
P\u0159\u00edtomnost ne\u010distot<\/td>\nNe\u010distoty mohou ovlivnit krystalovou strukturu a polarizaci.<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Aplikace pyroelektrick\u00e9ho efektu v piezo keramice<\/p>\n

Pyroelektrick\u00fd efekt v piezo keramice m\u00e1 \u0159adu aplikac\u00ed, nap\u0159\u00edklad:<\/p>\n

    \n
  • Infra\u010derven\u00e9 senzory:<\/strong> Pyroelektrick\u00e9 senzory jsou schopny detekovat infra\u010derven\u00e9 z\u00e1\u0159en\u00ed na z\u00e1klad\u011b zm\u011bny teploty zp\u016fsoben\u00e9 absorpc\u00ed z\u00e1\u0159en\u00ed.<\/li>\n
  • Termografie:<\/strong> Pyroelektrick\u00e9 senzory se pou\u017e\u00edvaj\u00ed v termografick\u00fdch syst\u00e9mech pro m\u011b\u0159en\u00ed teplotn\u00edch profil\u016f objekt\u016f.<\/li>\n
  • Pyrometr:<\/strong> Pro bezkontaktn\u00ed m\u011b\u0159en\u00ed vysok\u00fdch teplot.<\/li>\n<\/ul>\n

    Z\u00e1v\u011br<\/p>\n

    Pyroelektrick\u00fd efekt je d\u016fle\u017eit\u00e1 vlastnost piezo keramiky, kter\u00e1 nach\u00e1z\u00ed uplatn\u011bn\u00ed v r\u016fzn\u00fdch aplikac\u00edch. Jeho pochopen\u00ed je kl\u00ed\u010dov\u00e9 pro n\u00e1vrh a optimalizaci za\u0159\u00edzen\u00ed vyu\u017e\u00edvaj\u00edc\u00edch tento efekt. D\u016fle\u017eit\u00e9 je br\u00e1t v \u00favahu faktory, kter\u00e9 ovliv\u0148uj\u00ed velikost pyroelektrick\u00e9ho efektu, aby bylo mo\u017en\u00e9 dos\u00e1hnout optim\u00e1ln\u00edho v\u00fdkonu.<\/p>\n","protected":false},"excerpt":{"rendered":"

    Piezoelektrick\u00fd jev je dob\u0159e zn\u00e1m\u00fd u piezoelektrick\u00fdch materi\u00e1l\u016f, ale m\u00e9n\u011b diskutovan\u00fd je pyroelektrick\u00fd efekt, kter\u00fd se u n\u011bkter\u00fdch z nich, v\u010detn\u011b piezo keramiky, tak\u00e9 projevuje. Pyroelekt\u0159ina je vlastnost n\u011bkter\u00fdch materi\u00e1l\u016f, kter\u00e9 generuj\u00ed elektrick\u00fd n\u00e1boj v reakci na zm\u011bnu teploty. Tento \u010dl\u00e1nek se zam\u011b\u0159\u00ed na vysv\u011btlen\u00ed pyroelektrick\u00e9ho efektu v kontextu piezo keramiky. Struktura piezoelektrick\u00e9ho a pyroelektrick\u00e9ho<\/p>\n","protected":false},"author":1,"featured_media":543,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6415],"tags":[],"class_list":["post-63196","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\/63196","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=63196"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/posts\/63196\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media\/543"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/media?parent=63196"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/categories?post=63196"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/cs\/wp-json\/wp\/v2\/tags?post=63196"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}