{"id":54080,"date":"2022-08-29T04:35:25","date_gmt":"2022-08-29T09:35:25","guid":{"rendered":"https:\/\/www.bjultrasonic.com\/piezo-ceramics-how-to-define-strain\/"},"modified":"2025-01-21T07:25:38","modified_gmt":"2025-01-21T12:25:38","slug":"piezo-ceramics-how-to-define-strain","status":"publish","type":"post","link":"https:\/\/www.bjultrasonic.com\/vi\/piezo-ceramics-how-to-define-strain\/","title":{"rendered":"\u0110\u1ecbnh ngh\u0129a bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n"},"content":{"rendered":"<p>G\u1ed1m \u00e1p \u0111i\u1ec7n, m\u1ed9t lo\u1ea1i v\u1eadt li\u1ec7u th\u00f4ng minh v\u1edbi kh\u1ea3 n\u0103ng chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng c\u01a1 h\u1ecdc th\u00e0nh n\u0103ng l\u01b0\u1ee3ng \u0111i\u1ec7n v\u00e0 ng\u01b0\u1ee3c l\u1ea1i, \u0111\u00e3 v\u00e0 \u0111ang \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i trong nhi\u1ec1u l\u0129nh v\u1ef1c t\u1eeb c\u1ea3m bi\u1ebfn, thi\u1ebft b\u1ecb truy\u1ec1n \u0111\u1ed9ng \u0111\u1ebfn thu n\u0103ng l\u01b0\u1ee3ng.  Hi\u1ec3u r\u00f5 v\u1ec1 bi\u1ebfn d\u1ea1ng (strain) trong g\u1ed1m \u00e1p \u0111i\u1ec7n l\u00e0 ch\u00eca kh\u00f3a \u0111\u1ec3 t\u1ed1i \u01b0u h\u00f3a thi\u1ebft k\u1ebf v\u00e0 hi\u1ec7u su\u1ea5t c\u1ee7a c\u00e1c \u1ee9ng d\u1ee5ng n\u00e0y. B\u00e0i vi\u1ebft n\u00e0y s\u1ebd t\u1eadp trung ph\u00e2n t\u00edch v\u00e0 \u0111\u1ecbnh ngh\u0129a bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n, bao g\u1ed3m c\u00e1c kh\u00eda c\u1ea1nh l\u00fd thuy\u1ebft v\u00e0 th\u1ef1c nghi\u1ec7m.<\/p>\n<h3>\u0110\u1ecbnh ngh\u0129a bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n<\/h3>\n<p>Bi\u1ebfn d\u1ea1ng, n\u00f3i m\u1ed9t c\u00e1ch \u0111\u01a1n gi\u1ea3n, l\u00e0 s\u1ef1 thay \u0111\u1ed5i k\u00edch th\u01b0\u1edbc ho\u1eb7c h\u00ecnh d\u1ea1ng c\u1ee7a v\u1eadt li\u1ec7u khi ch\u1ecbu t\u00e1c \u0111\u1ed9ng c\u1ee7a m\u1ed9t l\u1ef1c b\u00ean ngo\u00e0i. Trong g\u1ed1m \u00e1p \u0111i\u1ec7n, bi\u1ebfn d\u1ea1ng n\u00e0y c\u00f3 th\u1ec3 \u0111\u01b0\u1ee3c t\u1ea1o ra b\u1edfi c\u1ea3 t\u00e1c \u0111\u1ed9ng c\u01a1 h\u1ecdc (\u1ee9ng su\u1ea5t) v\u00e0 t\u00e1c \u0111\u1ed9ng \u0111i\u1ec7n tr\u01b0\u1eddng.  Bi\u1ebfn d\u1ea1ng \u0111\u01b0\u1ee3c \u0111\u1ecbnh ngh\u0129a l\u00e0 t\u1ef7 l\u1ec7 thay \u0111\u1ed5i chi\u1ec1u d\u00e0i (\u0394L) so v\u1edbi chi\u1ec1u d\u00e0i ban \u0111\u1ea7u (L) c\u1ee7a v\u1eadt li\u1ec7u:<\/p>\n<p>Strain (\u03b5) = \u0394L \/ L<\/p>\n<h3>C\u00e1c lo\u1ea1i bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n<\/h3>\n<p>C\u00f3 nhi\u1ec1u lo\u1ea1i bi\u1ebfn d\u1ea1ng kh\u00e1c nhau trong g\u1ed1m \u00e1p \u0111i\u1ec7n, bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>Bi\u1ebfn d\u1ea1ng d\u1ecdc (Longitudinal strain):<\/strong> X\u1ea3y ra theo h\u01b0\u1edbng c\u1ee7a l\u1ef1c t\u00e1c d\u1ee5ng.<\/li>\n<li><strong>Bi\u1ebfn d\u1ea1ng ngang (Transverse strain):<\/strong> X\u1ea3y ra vu\u00f4ng g\u00f3c v\u1edbi h\u01b0\u1edbng c\u1ee7a l\u1ef1c t\u00e1c d\u1ee5ng.<\/li>\n<li><strong>Bi\u1ebfn d\u1ea1ng c\u1eaft (Shear strain):<\/strong> X\u1ea3y ra khi hai m\u1eb7t ph\u1eb3ng song song c\u1ee7a v\u1eadt li\u1ec7u tr\u01b0\u1ee3t l\u00ean nhau.<\/li>\n<\/ul>\n<table class=\"table table-striped table-bordered\">\n<thead>\n<tr>\n<th>Lo\u1ea1i bi\u1ebfn d\u1ea1ng<\/th>\n<th>M\u00f4 t\u1ea3<\/th>\n<th>C\u00f4ng th\u1ee9c<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>Bi\u1ebfn d\u1ea1ng d\u1ecdc<\/td>\n<td>Thay \u0111\u1ed5i chi\u1ec1u d\u00e0i theo h\u01b0\u1edbng l\u1ef1c<\/td>\n<td>\u03b5 = \u0394L \/ L<\/td>\n<\/tr>\n<tr>\n<td>Bi\u1ebfn d\u1ea1ng ngang<\/td>\n<td>Thay \u0111\u1ed5i chi\u1ec1u r\u1ed9ng vu\u00f4ng g\u00f3c v\u1edbi l\u1ef1c<\/td>\n<td>\u03b5 = \u0394W \/ W<\/td>\n<\/tr>\n<tr>\n<td>Bi\u1ebfn d\u1ea1ng c\u1eaft<\/td>\n<td>G\u00f3c bi\u1ebfn d\u1ea1ng gi\u1eefa hai m\u1eb7t ph\u1eb3ng<\/td>\n<td>\u03b5 = tan(\u03b3) \u2248 \u03b3 (v\u1edbi \u03b3 nh\u1ecf)<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h3>H\u1eb1ng s\u1ed1 \u00e1p \u0111i\u1ec7n v\u00e0 bi\u1ebfn d\u1ea1ng<\/h3>\n<p>C\u00e1c h\u1eb1ng s\u1ed1 \u00e1p \u0111i\u1ec7n \u0111\u00f3ng vai tr\u00f2 quan tr\u1ecdng trong vi\u1ec7c li\u00ean h\u1ec7 gi\u1eefa bi\u1ebfn d\u1ea1ng v\u00e0 \u0111i\u1ec7n tr\u01b0\u1eddng ho\u1eb7c \u1ee9ng su\u1ea5t.  V\u00ed d\u1ee5, h\u1eb1ng s\u1ed1 d33 m\u00f4 t\u1ea3 m\u1ed1i quan h\u1ec7 gi\u1eefa bi\u1ebfn d\u1ea1ng d\u1ecdc v\u00e0 \u0111i\u1ec7n tr\u01b0\u1eddng theo h\u01b0\u1edbng \u0111\u00f3.  M\u1ed9t \u0111i\u1ec7n tr\u01b0\u1eddng m\u1ea1nh h\u01a1n s\u1ebd t\u1ea1o ra bi\u1ebfn d\u1ea1ng l\u1edbn h\u01a1n, t\u1ef7 l\u1ec7 v\u1edbi h\u1eb1ng s\u1ed1 d33. T\u01b0\u01a1ng t\u1ef1, h\u1eb1ng s\u1ed1 d31 li\u00ean h\u1ec7 bi\u1ebfn d\u1ea1ng ngang v\u1edbi \u0111i\u1ec7n tr\u01b0\u1eddng d\u1ecdc.<\/p>\n<h3>Ph\u01b0\u01a1ng ph\u00e1p \u0111o l\u01b0\u1eddng bi\u1ebfn d\u1ea1ng<\/h3>\n<p>C\u00f3 nhi\u1ec1u ph\u01b0\u01a1ng ph\u00e1p \u0111\u1ec3 \u0111o l\u01b0\u1eddng bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n, bao g\u1ed3m:<\/p>\n<ul>\n<li><strong>Strain gauge:<\/strong> \u0110\u00e2y l\u00e0 ph\u01b0\u01a1ng ph\u00e1p ph\u1ed5 bi\u1ebfn v\u00e0 t\u01b0\u01a1ng \u0111\u1ed1i \u0111\u01a1n gi\u1ea3n, s\u1eed d\u1ee5ng m\u1ed9t c\u1ea3m bi\u1ebfn \u0111i\u1ec7n tr\u1edf d\u00e1n l\u00ean b\u1ec1 m\u1eb7t v\u1eadt li\u1ec7u \u0111\u1ec3 \u0111o s\u1ef1 thay \u0111\u1ed5i chi\u1ec1u d\u00e0i.<\/li>\n<li><strong>Giao thoa k\u1ebf laser:<\/strong>  Ph\u01b0\u01a1ng ph\u00e1p n\u00e0y cho \u0111\u1ed9 ch\u00ednh x\u00e1c cao h\u01a1n b\u1eb1ng c\u00e1ch \u0111o s\u1ef1 d\u1ecbch chuy\u1ec3n b\u1eb1ng giao thoa c\u1ee7a c\u00e1c ch\u00f9m tia laser.<\/li>\n<li><strong>Ph\u01b0\u01a1ng ph\u00e1p quang h\u1ecdc kh\u00e1c:<\/strong> Bao g\u1ed3m k\u1ef9 thu\u1eadt h\u00ecnh \u1ea3nh k\u1ef9 thu\u1eadt s\u1ed1 (DIC) \u0111\u1ec3 \u0111o bi\u1ebfn d\u1ea1ng to\u00e0n tr\u01b0\u1eddng.<\/li>\n<\/ul>\n<h3>\u1ea2nh h\u01b0\u1edfng c\u1ee7a c\u00e1c y\u1ebfu t\u1ed1 kh\u00e1c \u0111\u1ebfn bi\u1ebfn d\u1ea1ng<\/h3>\n<p>Bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n c\u0169ng b\u1ecb \u1ea3nh h\u01b0\u1edfng b\u1edfi c\u00e1c y\u1ebfu t\u1ed1 kh\u00e1c nh\u01b0 nhi\u1ec7t \u0111\u1ed9, t\u1ea7n s\u1ed1 c\u1ee7a \u0111i\u1ec7n tr\u01b0\u1eddng k\u00edch th\u00edch, v\u00e0 s\u1ef1 l\u00e3o h\u00f3a c\u1ee7a v\u1eadt li\u1ec7u.  Vi\u1ec7c xem x\u00e9t c\u00e1c y\u1ebfu t\u1ed1 n\u00e0y l\u00e0 c\u1ea7n thi\u1ebft \u0111\u1ec3 \u0111\u1ea3m b\u1ea3o \u0111\u1ed9 ch\u00ednh x\u00e1c v\u00e0 \u0111\u1ed9 tin c\u1eady c\u1ee7a c\u00e1c \u1ee9ng d\u1ee5ng.<\/p>\n<p>T\u00f3m l\u1ea1i, vi\u1ec7c hi\u1ec3u r\u00f5 v\u1ec1 bi\u1ebfn d\u1ea1ng trong g\u1ed1m \u00e1p \u0111i\u1ec7n, bao g\u1ed3m \u0111\u1ecbnh ngh\u0129a, c\u00e1c lo\u1ea1i bi\u1ebfn d\u1ea1ng, h\u1eb1ng s\u1ed1 \u00e1p \u0111i\u1ec7n li\u00ean quan v\u00e0 ph\u01b0\u01a1ng ph\u00e1p \u0111o l\u01b0\u1eddng, l\u00e0 r\u1ea5t quan tr\u1ecdng \u0111\u1ec3 thi\u1ebft k\u1ebf v\u00e0 t\u1ed1i \u01b0u h\u00f3a c\u00e1c \u1ee9ng d\u1ee5ng c\u1ee7a lo\u1ea1i v\u1eadt li\u1ec7u \u0111a n\u0103ng n\u00e0y.  Vi\u1ec7c nghi\u00ean c\u1ee9u v\u00e0 ph\u00e1t tri\u1ec3n c\u00e1c k\u1ef9 thu\u1eadt \u0111o l\u01b0\u1eddng v\u00e0 m\u00f4 h\u00ecnh h\u00f3a bi\u1ebfn d\u1ea1ng ti\u00ean ti\u1ebfn s\u1ebd ti\u1ebfp t\u1ee5c m\u1edf ra nh\u1eefng ti\u1ec1m n\u0103ng m\u1edbi cho g\u1ed1m \u00e1p \u0111i\u1ec7n trong t\u01b0\u01a1ng lai.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>G\u1ed1m \u00e1p \u0111i\u1ec7n, m\u1ed9t lo\u1ea1i v\u1eadt li\u1ec7u th\u00f4ng minh v\u1edbi kh\u1ea3 n\u0103ng chuy\u1ec3n \u0111\u1ed5i n\u0103ng l\u01b0\u1ee3ng c\u01a1 h\u1ecdc th\u00e0nh n\u0103ng l\u01b0\u1ee3ng \u0111i\u1ec7n v\u00e0 ng\u01b0\u1ee3c l\u1ea1i, \u0111\u00e3 v\u00e0 \u0111ang \u0111\u01b0\u1ee3c \u1ee9ng d\u1ee5ng r\u1ed9ng r\u00e3i trong nhi\u1ec1u l\u0129nh v\u1ef1c t\u1eeb c\u1ea3m bi\u1ebfn, thi\u1ebft b\u1ecb truy\u1ec1n \u0111\u1ed9ng \u0111\u1ebfn thu n\u0103ng l\u01b0\u1ee3ng. Hi\u1ec3u r\u00f5 v\u1ec1 bi\u1ebfn d\u1ea1ng (strain) trong<\/p>\n","protected":false},"author":1,"featured_media":5007,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6406],"tags":[],"class_list":["post-54080","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blog","prodpage-classic"],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/54080","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/comments?post=54080"}],"version-history":[{"count":0,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/posts\/54080\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media\/5007"}],"wp:attachment":[{"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/media?parent=54080"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/categories?post=54080"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.bjultrasonic.com\/vi\/wp-json\/wp\/v2\/tags?post=54080"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}