{"id":708,"date":"2015-06-10T09:49:42","date_gmt":"2015-06-10T07:49:42","guid":{"rendered":"https:\/\/sim.utcluj.ro\/wp\/?p=708"},"modified":"2015-06-24T08:53:41","modified_gmt":"2015-06-24T06:53:41","slug":"materialele-metalice-in-sec-xxi","status":"publish","type":"post","link":"https:\/\/sim.utcluj.ro\/materialele-metalice-in-sec-xxi\/","title":{"rendered":"MATERIALELE METALICE \u00een sec. XXI"},"content":{"rendered":"<p>Materialele metalice sunt esen\u0163iale pentru construc\u0163ia podurilor, cl\u0103dirilor sau a oric\u0103rui mijloc de transport: de la autoturisme p\u00e2n\u0103 la avioane sau navete spa\u0163iale. Tradi\u0163ia prelucr\u0103rii metalelor are o istorie \u00eendelungat\u0103, de la f\u0103urirea s\u0103biilor de samurai, a armurilor la realizarea implanturilor medicale, a super-aliajelor utilizate \u00een industria aerospa\u0163ial\u0103 sau a aliajelor cu memorie. Aceste realiz\u0103ri moderne ale ingineriei materialelor au fost posibile datorit\u0103 \u00een\u0163elegerii la un nivel avansat a structurii materialelor \u015fi a capacit\u0103\u0163ii de procesare a acestora.<\/p>\n<p>\u00cen materialul video de mai jos este ilustrat\u0103 o aplica\u0163ie interesant\u0103 a materialelor metalice inteligente care sunt folosite pentru ventila\u0163ia natural\u0103 a cl\u0103dirilor moderne. Uzual spa\u0163iile \u015fi cl\u0103dirile pentru birouri sau locuin\u0163e sunt mari consumatoare de energie pentru asigurarea unui confort termic. Folosind \u00een arhitectura modern\u0103 materiale bimetalice cu propriet\u0103\u0163i termice speciale, acestea ac\u0163ioneaz\u0103 precum pielea omului av\u00e2nd o comportare dinamic\u0103 \u00een func\u0163ie de temperatur\u0103 \u015fi asigur\u0103 \u00een mod inteligent procesul de auto-ventilare a cl\u0103dirii f\u0103r\u0103 consum de energie. Astfel, se reduc emisiile de carbon, consumul de energie \u00een condi\u0163iile \u00een care este asigurat \u015fi confortul termic.<\/p>\n<p><iframe src=\"https:\/\/embed-ssl.ted.com\/talks\/lang\/ro\/doris_kim_sung_metal_that_breathes.html\" width=\"640\" height=\"360\" frameborder=\"0\" scrolling=\"no\" allowfullscreen=\"allowfullscreen\"><\/iframe><\/p>\n<p>Sectoare extrem de importante ale economiei se bazeaz\u0103 pe rezisten\u0163a \u015fi propriet\u0103\u0163ile metalelor f\u0103r\u0103 de care nu am dispune de energie nuclear\u0103, energie electric\u0103, de infrastructuri precum zgarie-norii, locuin\u0163e, birouri, fabrici sau mijloace de transport de orice fel. Nu s-ar putea imagina o civiliza\u0163ie avansat\u0103 f\u0103r\u0103 materialele metalice. Speciali\u015ftii din domeniul ingineriei materialelor sunt cei care proiecteaz\u0103, execut\u0103 noi aliaje, tehnologii de procesare pentru ca acestea s\u0103 ating\u0103 performan\u0163e tot mai ridicate \u00een toate sectoarele economiei. Speciali\u015ftii din domeniul Ingineria \u015fi Protec\u0163ia Mediului sunt chema\u0163i s\u0103 asigure respectarea condi\u0163iilor de protec\u0163ia mediului \u00een procesele complexe de elaborare \u015fi procesare a materialelor, \u00een procesele de reciclare a materialelor. \u00cenpreun\u0103, to\u0163i ace\u015fti speciali\u015fti sunt preg\u0103ti\u0163i pentru provoc\u0103rile secolului XXI, \u00een cadrul Facult\u0103\u0163ii de Ingineria Materialelor \u015fi a Mediului, cea mai bun\u0103 facultate din \u0163ar\u0103 \u00een domeniul Ingineriei Materialelor, conform clasific\u0103rii Asocia\u0163iei Universit\u0103\u0163ilor Europene.<\/p>\n<p>Metalele sunt caracterizate de maleabilitate, ductilitate, conductivitate electric\u0103 \u015fi termic\u0103 ridicat\u0103, suprafa\u0163a lucioas\u0103 a acestora reflect\u00e2nd lumina. Sunt caracterizate de o leg\u0103tur\u0103 metalic\u0103 \u00eentre atomi, ceea ce permite ca electronii de valen\u0163\u0103 s\u0103 fie partaja\u0163i de tot corpul metalic. Astfel, datorit\u0103 electronilor care se pot deplasa prin re\u0163eau cristalin\u0103, ace\u015ftia determin\u0103 propriet\u0103\u0163ile excelente de conductivitate termic\u0103 \u015fi electric\u0103 specifice metalelor.<\/p>\n<p>Uzual, metalele \u015fi aliajele acestora au o structur\u0103 cristalin\u0103, ceea ce reprezint\u0103 elementul cheie pentru a asigura caracteristicile de rezisten\u0163\u0103 necesare \u00een aplica\u0163iile amintite. De exemplu structura metalic\u0103 a avioanelor se deformeaz\u0103 elastic la viteze \u015fi altitudini ridicate, la fel structura de rezisten\u0163\u0103 a submarinelor care se deformeaz\u0103 o dat\u0103 cu cre\u015fterea ad\u00e2ncimii de imersie sau zg\u00e2rie norii care se unduiesc sub influen\u0163a v\u00e2ntului. \u00cen aceste exemple este ilustrat\u0103 capacitatea metalelor de a se deforma elastic sub sarcin\u0103 \u015fi de a oferi rezisten\u0163a necesar\u0103 pentru ca structura metalic\u0103 s\u0103 fac\u0103 fa\u0163\u0103 solicit\u0103rilor foarte mari.<\/p>\n<p>Mai recent, aplica\u0163iile \u00een domeniul nanotehnologiilor au revolu\u0163ionat modul nostru de a privi aceste metale \u015fi cum pot schimba fundamental tot ce se credea la un moment dat c\u0103 este posibil. Aplica\u0163ii care par desprinse din lumea SF ast\u0103zi sunt transformate \u00een realitate cu ajutorul speciali\u015ftilor din domeniul ingineriei materialelor. La scar\u0103 nanometric\u0103, electronii manifest\u0103 ca \u015fi fotonii un caracter ondulatoriu, materialele metalice c\u0103p\u0103t\u00e2nd propriet\u0103\u0163i complet diferite fa\u0163\u0103 de cele cunoscute la nivel macroscopic. De exemplu particulele de argint sunt galbene, iar cele din aur sunt ro\u015fiatic \u00eenchis. Aceste noi propriet\u0103\u0163i optice sunt interesante \u00een tehnologiile IT \u015fi de comunica\u0163ii.<\/p>\n<p>Material realizat de S.L. dr.ing. Bodea Marius<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Materialele metalice sunt esen\u0163iale pentru construc\u0163ia podurilor, cl\u0103dirilor sau a oric\u0103rui mijloc de transport: de la autoturisme p\u00e2n\u0103 la avioane [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"gallery","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[1],"tags":[22,16],"class_list":["post-708","post","type-post","status-publish","format-gallery","hentry","category-materiale","tag-materiale-inteligente","tag-mediu","post_format-post-format-gallery"],"_links":{"self":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/708","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/comments?post=708"}],"version-history":[{"count":4,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/708\/revisions"}],"predecessor-version":[{"id":754,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/posts\/708\/revisions\/754"}],"wp:attachment":[{"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/media?parent=708"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/categories?post=708"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/sim.utcluj.ro\/wp-json\/wp\/v2\/tags?post=708"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}