Pamene cholumikizira chikulephera, masitepe athu oyamba amaphatikizapo kuyesa ngati mphamvu zomatira ndizokwanira, chithandizo chapamwamba ndi choyenera, kulowetsedwa ndikokwanira, ndipo zipangizozo sizinakalamba.
Komabe, pamagwiritsidwe enieni a uinjiniya, zolephera zina sizimangoyamba pakutumidwa; m'malo mwake, zoopsa zomwe zingakhalepo zilipo kale zomatira zikatha kuchiritsidwa.
Chowopsa ichi ndi kukhalapo kwa kupsinjika kotsalira kwamkati.
Ndizosaoneka komanso zovuta kuziyeza ndendende mwachindunji, koma osati zachinsinsi m'chilengedwe. Mwachidule, zomatira zimachepa pakuchiritsa ndi kuziziritsa; ngati gawo lapansi lozungulira limaletsa kusinthika kwake kwaulere, gawo losasunthika limakhala kupsinjika kotsalira mkati mwa zomatira.
Lero, ndikutsogolerani nonse kuti mumvetse bwino mfundo imeneyi.
0 1 Chifukwa chiyani muyenera kuphunzira?
Zowopsa za kupsinjika kwamkati ndi za "mphamvu-zosungirako" chikhalidwe.
Akachiritsa, zomatirazo zimasunga gawo la mphamvu zotanuka. Mphamvu imeneyi imakhala ngati mphamvu yoyendetsera delamination yotsatila, kufalitsa kwa microcrack, ndi warping deformation.
Tengani mawonekedwe a delamination ndi delamination monga zitsanzo: zovuta zamkati zimachulukana pamwamba pa ntchito, zomwe zimapangitsa kuti mawonekedwe ake asokonezeke kwambiri kuposa momwe adapangira-mtengo wowerengetsera. M'mawu ena, ngakhale zomatira zisanayambe ntchito, mawonekedwe ake amakhala kale ndi vuto lalikulu la -pambuyo pake.
Chitsanzo china ndi kutsetsereka kolondola, komwe kumawononga makamaka makonzedwe olondola monga maloboti, ma mota, ndi zida zowonera.
Malo a maginito core mu mota, kayitanidwe ka zinthu zowoneka bwino, ndi makulidwe a zigawo zonse zitha kugwedezeka kwa nthawi yayitali-chifukwa cha kutulutsa kwapang'onopang'ono kwa zovuta zamkati. Ngati zigawozo zimagwirizana poyambira koma zimasokonekera pakatha maola mazana ambiri zikugwira ntchito, zovuta zotere zimayamba chifukwa cha zovuta zamkati.
Kuonjezera apo, moyo wotopa umachepetsedwa. Kupsinjika kwamkati kumayimira-kupsinjika kwanthawi yayitali komwe kumachepetsa kutopa kwanthawi yayitali. Kuphatikiza kwa kutentha kwa njinga, chinyezi, ndi kugwedezeka nthawi zambiri kumabweretsa zinthu zomwe zimayesedwa koyambirira koma zimalephera panthawi yopanga zochuluka.
Chifukwa chake, kupsinjika kwamkati si nkhani yachiwiri koma ndikofunikira kuti pakhale mgwirizano wodalirika. Imatsimikizira osati kokha ngati kumamatira kungathe kuchitika, komanso nthawi yayitali bwanji chomangiracho chimakhala chokhazikika pambuyo pake.
0 2 Kodi nkhawa zamkati zimayambira kuti?
Kuti timvetse kupsinjika kwa mkati, munthu ayenera kumvetsetsa kaye chiyambi chake.
Kupsyinjika kwamkati mkati mwa zomatira kumachokera ku mitundu iwiri ya mitundu yomwe imasonyeza chizolowezi chomangika koma sichingathe kutero.
Gulu loyamba ndikuchiritsa kuchepa, komwe kumadziwikanso kuti shrinkage yamankhwala.
Mu ma monomers amadzimadzi, mamolekyu amalumikizana kudzera mu mphamvu za van der Waals (zofooka). Palibe mgwirizano wamankhwala pakati pa ma atomu a mamolekyu awiri; zimangokhalapo moyandikana, ndi mtunda wofanana ndi 0.3-0.4 nm (umene umayimira kuchuluka kwa ma van der Waals radii a mamolekyu onse awiri).
Pa polymerization anachita, covalent zomangira aumbike pakati monomers. Kutengera chomangira chodziwika bwino cha C-C mwachitsanzo, kutalika kwake ndi pafupifupi 0.154 nm. Izi zikutanthauza kuti mamolekyu awiri omwe analekanitsidwa poyamba ndi mtunda wotakasuka wa pafupifupi 0.35 nm tsopano asonkhanitsidwa pamodzi ndi covalent chomangira chautali pafupifupi 0.15 nm-kuchititsa kuti mtunda wa intermolecular uchepe ndi kupitirira theka. (Chithunzi)
Pamlingo waukulu kwambiri, kufupikitsa kwa ma thililiyoni mabiliyoni a ma molekyulu oterowo kumawoneka ngati kutsika kwamphamvu. Ichi ndi chotsatira chakuthupi chomwe sichingapewedwe muzowonjezera zilizonse za polymerization.
Gulu lachiwiri ndi kupsinjika kwa kutentha kosagwirizana.
Zomatira zambiri zimafunikira kutentha kuti zichiritsidwe. Pambuyo kuchiritsa, utakhazikika kuchokera kutentha kwa kutentha kwa firiji, mawotchi owonjezera ma coefficients a zomatira ndi gawo lapansi amasiyana.
Kukula kowonjezera kwamafuta kumamatira nthawi zambiri kumakhala kokwera kwambiri kuposa zinthu zoyambira monga zitsulo, maginito, ndi zoumba. Panthawi yozizira, zomatirazo zimakonda kuphatikizika, koma maziko ake amalepheretsa kuphatikizika kwake kwaulere, potero amaletsa zomatira ndikupangitsa kupsinjika kotsalira kwamkati.
Lingaliro lovuta kwambiri apa ndi mfundo ya gel.
Isanafike nsonga ya gel, zomatira zimakhala zamadzimadzi ndipo zimatha kuyenda. Panthawi imeneyi, ngakhale kutsika kukuchitika, zinthuzo zimatha kusokoneza kusinthika koteroko kudzera mukuyenda, kukonzanso, ndi kudzaza, potero kuchepetsa kudzikundikira kwa kupsinjika kwa mkati.
Pambuyo pa gel osakaniza, zinthu zimasintha. Ma network atatu-amayamba kupangika mkati mwa zomatira, ndipo zinthu zimasintha pang'onopang'ono kuchoka pamadzi kukhala olimba. Pakadali pano, zomatira zimalemera-kutha kunyamula ndipo zimayamba "kukumbukira" kuchulukira kotsatira ndi kupindika.
Mwa kuyankhula kwina, gawo la contraction lomwe limachitika pambuyo pa gel osakaniza limakhala losavuta kutulutsa kupsinjika kwamkati.
Pamene nthawi ikupita, zinthuzo zimalimba kwambiri, ndipo Tg yake imakwera mosalekeza. Pamene Tg idutsa kutentha kwaposachedwa, zomatira zimasintha kuchoka ku rubbery kupita ku galasi.
Polowa mu galasi, modulus ya zomatira wosanjikiza amakula mofulumira, kupanga unyolo gawo kuyenda movutikira; chifukwa chake, gawo lina la nkhawa lomwe likanatha kumasulidwa limakhala lovuta kwambiri kumasula.
Chifukwa chake, kupsinjika kwamkati kumatha kumveka ngati:
Pamaso pa gel osakaniza: kutsika kumatha kuchitika popanda kuyambitsa kupsinjika.
Pambuyo pa mfundo ya gel: wosanjikiza wa gel osakaniza umayamba kupanga maukonde, ndipo shrinkage yotsatira imaletsedwa.
Pambuyo pa vitrification: zinthuzo zimakhala zolimba, ndi maunyolo a maselo osasunthika, zomwe zimapangitsa kuti kupanikizika kumasulidwe kukhala kovuta kwambiri.
Monga tonse tikudziwa:
Kupanikizika=Modulus × Kupsyinjika
Kupsinjika komaliza kwamkati ≈ modulus yogwira mtima × (post-gelation curing shrinkage + thermal mismatch deformation) − kumasuka
Kutentha kosagwirizana ndi kutentha kumatha kumveka ngati:
Kutentha kosagwirizana ndi kutentha ≈ (kuwonjezera kutentha kwa zomatira - kuchuluka kwa kutentha kwa gawo lapansi) × kusiyana kwa kutentha kwapakati
Kutsika kokha ndi kusagwirizana kwamafuta komwe kumachitika pambuyo pa gel osakaniza, kuchulukitsidwa ndi modulus yomwe ikuchulukirachulukira, kuchotseratu gawo lomwe limatulutsidwa kudzera pakupumula panthawiyi, kumapanga kupsinjika komaliza kwamkati.
Ichi ndi chifukwa chakenso kupsinjika kwamkati kumakhala kovuta kuphunzira: sikumatuluka mwadzidzidzi panthawi imodzi koma kumachulukana pang'onopang'ono panthawi yochiritsa ndi kuziziritsa. Panthawi yonseyi, kuchepa, kutentha, modulus, ndi kuthekera kwazinthu kumasula kupsinjika zonse zimasintha mosalekeza.
03 Momwe mungadziwire: Choyamba yezani "zotsatira," kenako yezani "choyambitsa."
Tsopano zimadziwika kuti kupsinjika kwa mkati sikungochitika mwadzidzidzi, koma kumachulukana pang'onopang'ono panthawi yochiritsa ndi kuziziritsa.
Gawo lililonse pano likusintha mosalekeza: kuchuluka kwa kutsika, kutentha, modulus, komanso kuthekera kwazinthu kutulutsa kupsinjika kumasiyana.
Choncho, mawonekedwe a kupsinjika kwamkati sikungathe kudalira chiwerengero chimodzi chokha; iyenera kuyankha mafunso awiri nthawi imodzi:
Choyamba, ndi kuchuluka kwa nkhawa kapena kusinthika kotani komwe kumatsalira kumapeto?
Chachiwiri, kodi kupsyinjika kumeneku kumapangidwa bwanji panthawi yochiritsa?
Ponena za njira zoyesera, zimatha kugawidwa m'magulu awiri.
Gulu limodzi limaphatikizapo kuyeza kwachindunji kwa zotsatira za kupsinjika kapena kusintha, pomwe lina limayesa magawo amkati kuti akhazikitse zitsanzo.
Gulu 1: Kuyeza kwachindunji kwa zotsatira za kupsinjika kapena kusinthika
Njirayi imayang'ana pakuzindikira kuchuluka kwa kupindika kapena kupsinjika kotsalira komwe kumapangidwa mu kapangidwe kamene kamamatira kuchira.
Njira yachikale kwambiri ndi njira yopindika ya cantilever kapena bimaterial beam. Zomatira zimagwiritsidwa ntchito pazitsulo zopyapyala, zowotcha za silicon, kapena zinthu zina zapansi; pa kuchiritsa, zomatira shrinkage kumapangitsa gawo lapansi kupinda. Poyesa kupindika munthawi yeniyeni ndikugwiritsa ntchito njira yofananira ndi Stoney's equation, kupsinjika kwapakati pa zomatira kumatha kuwerengedwa. Njira imeneyi imapereka ubwino wokhala mwachidziwitso komanso{3}}kukhazikika bwino, kupangitsa kuti ma curve awonetsere momwe kupsinjika kumasiyanirana ndi nthawi yochira.
Palinso njira ya fiber Bragg grating (FBG). Mwa kuyika ulusi wa kuwala mkati mwa gel wosanjikiza, kupsyinjika mkati mwa gel kungathe kuyezedwa mu nthawi yeniyeni. Njirayi imapereka chithunzithunzi cholondola cha momwe gel alili mkati mwake poyerekeza ndi miyeso yosinthika ya pamwamba yokha, ngakhale imakhala ndi ndalama zambiri komanso zovuta zogwirira ntchito.
Chiritsani kuwunika kwa zovuta m'ma laminates ophatikizika pogwiritsa ntchito sensa yophatikizika (chithunzi chazithunzi)
Pazomatira zowonekera, njira za photoelasticity kapena birefringence zitha kugwiritsidwanso ntchito kuyang'anira kufalikira kwa kupsinjika pogwiritsa ntchito kupsinjika-induced birefringence.
Kuonjezera apo, njira monga kubowola, core sampling, X-ray diffraction (XRD), neutron scattering, ndi Raman shift analysis ingagwiritsidwenso ntchito pansi pazikhalidwe zinazake poyesa kupanikizika kotsalira kapena kupsyinjika kosalunjika.