Mawonekedwe a masangweji opangidwa ndi Copper-deposited carbon fiber aluminium foam foam sandwich poyerekeza ndi sangweji wamba wa aluminium thovu

Sandwich ya aluminium thovu(AFS) mapanelo ali ndi mawonekedwe ophatikizika komanso magwiridwe antchito monga kachulukidwe kakang'ono, mphamvu zapadera, kuyamwa bwino kwamphamvu, kutsitsa mphamvu, ndi chitetezo chamagetsi. Zinthu zabwinozi zimapangitsa AFS kukhala ndi kuthekera kwakukulu muzamlengalenga, mayendedwe, ndi minda yam'madzi. Poyerekeza ndi thovu lachitsulo, mbale zachitsulo zakunja za AFS zimatha kusindikiza thovulo ndikuwongolera mawonekedwe ake amakina, monga kulimba ndi kupindika. Nthawi zambiri, AFS idapangidwa ndi njira yomata yomata, yomwe imaphatikizapo kumangirira chithovu cha aluminiyamu ku mapanelo olimba azitsulo pogwiritsa ntchito zomatira za epoxy resin.

Ngakhale njira yomangira yomatira imakulitsa bwino kuwonongeka kwa kapangidwe kake, imatsagana ndi zolepheretsa, kuphatikiza zovuta pakubwezeretsanso komanso kukhala pachiwopsezo cha kulephera kwa delamination pansi pa kutentha kwambiri kapena nyengo ya dzimbiri. Pofuna kuthana ndi zofooka izi, kafukufuku wochuluka waperekedwa kuti akwaniritse mgwirizano wazitsulo pakati pa gulu ndi core layer.

Pakadali pano, njira zazikulu zokonzekera za AFS zomwe cholinga chake ndi kukwaniritsa mgwirizano wazitsulo nthawi zambiri zimagawidwa m'magulu atatu: kuwotcherera, kuwotcherera, kusungunula thovu, ndi kulongedza njira yazitsulo. Mwa njirazi, njira yolongedza zitsulo zonyamula katundu imawonedwa ngati yabwino kwambiri pakuwongolera kapangidwe ka pore ndikukwaniritsa thovu lotsika. Ntchito yathu yam'mbuyomu idagwiritsa ntchito ukadaulo uwu kupanga ma AFS akulu akulu okhala ndi katundu wokulirapo komanso mawonekedwe am'manja ogwiritsira ntchito mafakitale.

Komabe, chifukwa cha kuchepa kwamphamvu kwamakina a thovu pachimake, kusintha kwa mphamvu zamakina a AFS kumakhala kochepa, kotero kupititsa patsogolo mphamvu ya chithovu ndikofunikira kwambiri kwa AFS.

Mpaka pano, wamba njira lipoti kusintha compressive makina katundu waaluminium thovundi awa: mankhwala pamwamba, kutentha mankhwala, ndi kulimbikitsa powonjezera particles, ulusi, zinthu alloying, etc. Pakati pawo, ulusi wa carbon yochepa ndi otsika kachulukidwe, mkulu zotanuka modulus, ndi lalikulu mbali chiŵerengero chakopa chidwi kwambiri monga zingamuthandize kulimbikitsa zipangizo. Komanso, pamwamba zitsulo za carbon ulusi, ndi electroplating kapena mankhwala plating monga mkuwa plating kapena faifi tambala plating, kupititsa patsogolo wettability wa carbon ulusi mu zotayidwa kusungunuka ndi kupewa zoipa zimachitika pakati pa mpweya ulusi ndi zotayidwa kusungunuka. Mpweya wa carbon waufupi tsopano umagwiritsidwa ntchito kwambiri kulimbitsa ma aluminium matrix composites.

Bhav Singhetal. adakonza ulusi wa kaboni wokhala ndi mkuwa wolimbitsa ma aluminium matrix composites ndi njira yoponyera. Muetal. zopangidwa ndi aluminiyamu matrix composites zolimbikitsidwa ndi ulusi wa kaboni wokhala ndi nickel pogwiritsa ntchito njira yoponyera mipukutu iwiri. Zotsatirazo zinawonetsa kuwonjezereka kwakukulu kwa mphamvu zolimba za zophatikizika ndi kuwonjezera kwa carbon fibers. Komabe, pakhala pali kafukufuku wochepa wochitidwa pachithovu cha aluminiyamu chowonjezeredwandi ulusi wa kaboni wokhala ndi mkuwa. Caoetal. ulusi woyamba wopangidwa ndi kaboni wokhala ndi mkuwa unalimbitsa thovu la aluminiyamu kudzera munjira yosungunula thovu. Zotsatira zikuwonetsa kuti 0.35 vol% ya Cf imatha kukhazikika chithovu cha aluminiyamu poletsa kuphulika kwa filimu yamadzimadzi, ndipo kuchuluka kwa ulusi wowonjezera ku thovu kumakhala kokhazikika. Muetal. adawonetsa kuti zonyowa za thovu la aluminiyamu zokonzedwa ndi njira yosungunula thovu zidasinthidwa kwambiri ndikuwonjezera kwa Cf.

Chifukwa chake, titha kunena kuti kuwonjezera kwa Cf kungakhale njira yabwino yopititsira patsogolo kukhazikika kwa thovu ndi makina amakina.zitsulo za aluminiyamu. Kuphatikiza apo, sipanakhalepo malipoti okhudza ulusi wa kaboni wopangidwa ndi mkuwa womwe umalimbitsa masangweji a aluminium thovu okonzedwa kudzera mu njira ya zitsulo za ufa, zomwe zimalimbikitsa ochita kafukufuku kuti achite kafukufuku wozama pankhaniyi.

Kafukufuku wambiri wachitika pa nucleation limagwirira ndi kukhazikika kwazitsulo za aluminiyamundi kuwonjezera magawo olimbikitsa. Kusiyana kwa pore morphology ndi pore morphology,

monga kukula, kugawa, ndi mawonekedwe, nthawi zambiri zimatchedwa nucleation systems ndi kukhazikika. Heterogeneous nucleation effects ndi oxide network stabilization systems mu powder metallurgy system yafufuzidwa mozama. Quaternary alloy powders opangidwa ndi Al-Si-Mg-Cu omwe amagwiritsidwa ntchito m'mapepalawa awonetsa kufalikira kwapadera komanso kutentha kochepa kwa thovu, ndi kutentha kwa solidus 507 ◦C ndi kutentha kwa liquidus 596 ◦C. Komabe, palibe kafukufuku wokhudzana ndi makina a nucleation, kukhazikika, ndi makina ophatikizika a ma compact compact omwe ali ndi aloyi, makamaka akaphatikiza CF. M'ntchito zam'mbuyomo, kufufuza kwa nucleation ndi stabilization systems kunkachitika makamaka pogwiritsa ntchito njira zomwe sizinali mu situ, kuphatikizapo kusanthula tomographic kwa zitsanzo zomwe zinazizidwa mofulumira potsatira kusokonezeka kwa thovu. Tsoka ilo, submicron bubble nucleation imachitika pakuwotcha koyambilira ndipo imakula mwachangu pakapita nthawi kuchokera pa 100 ms mpaka 1 s, zomwe nthawi zambiri zimabweretsa zovuta pakuwonera nthawi yeniyeni. Njira yamakono ya synchrotron radiation X-ray imaging ili ndi mphamvu zambiri komanso kusinthika kwapakatikati, komwe kumalola kuwona nthawi yeniyeni, mkati mwa situ ya nucleation ndi kukula kwa thovu la aluminiyamu pa kutentha kokwera. Pakalipano, ofufuza ochepa okha ndi omwe adafufuza ma kinetics a Al-Si-Mg alloy powder ndi ma synchrotron radiation. Mwachitsanzo, García-Morenoetal. Adanenanso zochitika zazikulu zamphamvu mu thovu la aluminiyamu yamadzimadzi, kuphatikiza ma nucleation ndi kukula, kukonzanso kuwira, kubweza kwamadzi, kuphatikizika, ndi kuphulika kwa filimu. Kamm et al. adaphunzira za nucleation ndi kukula kwa foam ya aluminiyamu ya AlSi8Mg4 ndi ma radiation ya synchrotron. Zomwe anapeza zimasonyeza kuti haidrojeni yomwe imapangidwa chifukwa cha kuwonongeka kwa adsorbates pamtunda wa ufa wachitsulo ndi njira ina yofunika kwambiri yopangira nucleation. Komabe, kuyanjana pakati pa zigawo zoyambilira ndizovuta, ndipo kusinthika kwa thovu kumatha kutengera kapangidwe kake. Pazinthu zonse za Al-Si-Cu-Mg powder system ndi Al-Si-Cu-Mg powder system yowonjezeredwa ndi Cf, kumvetsetsa ndikuwunika kuyambika ndi kukula kwa thovu lachitsulo ndikofunikira kuti chithovucho chipitirire patsogolo za mapulogalamu.

Mu ntchitoyi, CF/AFS ndi AFS yokhala ndi zitsulo zolumikizana ndi zitsulo zinakonzedwa ndi njira yolongedza zitsulo za ufa. Kusintha kwa thovu la Cf/AFS ndi AFS kudawonedwa mu situ ndi ma radiation ya synchrotron kuwulula makina a Cf pa kuwira nucleation, kukula ndi kuphatikiza, ndi kukhazikika. Kuonjezera apo, Cf/AFS ndi AFS zinafufutidwa thovu pa 620 ◦C kwa 15 min mu ng'anjo ya chipinda. Pambuyo pake, kugawa kukula kwa pore, pore microstructure, ndi compressive mechanical properties of the foamed samples adadziwika ndikuyesedwa. Kutengera ndi maphunziro omwe tawatchulawa, kapangidwe kake ndi mphamvu zopondereza za Cf/AFS ndi AFS zidawunikidwa mwadongosolo.

2. Zida ndi njira

2.1. Zida zogwiritsira ntchito

Zida zisanu ndi chimodzi zidagwiritsidwa ntchito pokonzekera AFS ndi Cf / AFS: Al ufa (kukula kwapakati: 45 μm, chiyero> 99.70%), Si ufa (kukula kwapakati: 38 μm, chiyero> 99.50%), Cu ufa (kukula kwapakati: 38 μm, kuyera> 99.90%), Mg ufa (avereji kukula: 75 μm, chiyero > 99.70%), TiH2 ufa (avareji kukula: 45 μm, chiyero > 99.70%), ndi mpweya wopaka mkuwa (kukula kwake: 1 ~ 2 mm, makulidwe a mkuwa: 1.4 μm).

2.2. Kupanga kwa CF/AFS

Chiwembu cha njira yolongedza ufa wa chitsulo chikuwonetsedwa muChithunzi 1. Panthawi yosakaniza, ufa wa quaternary AlSi6Mg4Cu4 ufa unakonzedwa, ndi ufa wa Al, Si, Cu, ndi Mg mu 86 wt%, 6 wt%, 4 wt%, ndi 4 wt%, motero. 1 wt% oxidized TiH2 powder (mankhwala otentha mu mpweya kwa 1.5 h pa 470 ◦C) anawonjezeredwa ngati wothandizira wowomba omwe amamasula H2 mofulumira pa kutentha kusungunuka kukulitsa kusungunuka. Kuonjezera apo, 0.5 wt% ya carbon fibers adaphatikizidwa ngati magawo olimbikitsa. Makamaka, kuti apititse patsogolo kunyowa ndikupewa zovulaza ngati Al4C3 pa mawonekedwe a fiber-aluminiyamu yosungunuka pakuchita thovu, ulusi wa kaboni unali wokutidwa ndi mkuwa kudzera pa electroplating. Njira ya electroplating idafotokozedwa mu Refs.Chithunzi 2ikuwonetsa ulusi wa kaboni wokhala ndi mkuwa womwe umapezeka ndi njira yopangira ma electroless plating. Chophimbacho chimakhala ndi kuphimba kofanana komanso kosalekeza kwa fiber pamwamba(Mku. 2(a)–(b)). Pambuyo pake, mitundu yosiyanasiyana ya aloyi yomwe idagwiritsidwa ntchito mu phunziroli idakonzedwa ndikusakaniza ufa womwe tatchulawu ndi wopanda Cf mu chosakanizira chamagulu atatu kwa maola atatu. Ufa wosakanizidwa wofananawo umakutidwa mkati mwa chibowo chotsekedwa, ndikutsatiridwa ndi njira zozizira komanso zotentha.

Kuzizira kozizira kumatulutsa mpweya kuchokera mkati mwa mphako ndi malo ozungulira pakati pa tinthu tating'onoting'ono kudzera m'mipata yambiri ndi kupsinjika kwazing'ono. Gawo lotentha lopukutira limatsimikizira kuti cholozeracho chimakwaniritsa kuchuluka kwapang'onopang'ono kuposa 98% kudzera pakuphatikizana kwa gulu ndi ufa, zomwe zimathandizira kutulutsa thovu kotsatira. Tsatanetsatane wogubuduza magawo akufotokozedwa mu Refs. AFS ndi Cf/AFS foamable precursors amapezeka kudzera m'njira zomwe tafotokozazi. Pamapeto pake, ma precursors onse omwe amawotcha thovu adatenthedwa pa 620 ◦C kwa mphindi 15 kuti apange zitsanzo za Cf/AFS ndi AFS, zomwe zidagwiritsidwa ntchito poyesa kukula kwa pore, mawonekedwe a microstructural, ndi kuyesa kwamphamvu kwamakina.

2.3. Makhalidwe ndi njira zoyesera

2.3.1. Makhalidwe a Microstructural

Microstructure morphology ya Cf/AFS ndi AFS idafufuzidwa ndi ma electron microscopy (SEM, Zeiss Ultra Plus). Energy dispersive spectroscopy (EDS) idagwiritsidwa ntchito kuzindikira mawonekedwe a magawo osiyanasiyana m'makoma a cell a zitsanzo za thovu. Zigawo zautali za zitsanzozo zinapezedwa mwa kudula zitsanzo za thovu pogwiritsa ntchito makina otulutsa electro-discharging (EDM, DK7745). Pambuyo pa izi, zigawo zautali za zitsanzozo zidakutidwa ndi penti ndiyeno nkuzipaka mchenga ndi kupukuta pogwiritsa ntchito sandpaper ya 800-grit ndi 1500-grit. Pamapeto pake, ma diameter ofanana a cell (Dmean) a gawo lopukutidwa lachitsanzo adatsimikiziridwa pogwiritsa ntchito pulogalamu yosanthula zithunzi, Image Pro Plus 6.0.

Chithunzi 1.Schematic wa kulongedza kugubuduza ufa zitsulo njira.

Chithunzi 2.Zithunzi za SEM za (a) zitsulo za kaboni zokutidwa ndi mkuwa, ndi (b) zikuwonetsa kukwezedwa kwa dera lomwe lili ndi masikweya ofiira mu (a). Zithunzi (c) ndi (d) ndi zotsatira za EDS za mfundo A mu (b).

Chithunzi 3.Chithunzi chojambula cha kuyesa kwa synchrotron radiation.

2.3.2. Kuwona kwa thovu mu-situ ndi ma radiation ya synchrotron

Chithunzi chojambula cha kuyesa kwa synchrotron radiation chikujambulidwaChithunzi 3. Kuyeseraku kunachitika pa beamline 4W1A ya Beijing Synchrotron Radiation Facility (BSRF, Beijing Institute of High Energy Physics, Chinese Academy of Sciences, China). Mosiyana ndi kuyerekezera kosiyana kofananira, pepalali limagwiritsa ntchito kuyerekeza kwa magawo ndi Synchrotron Radiation Light Source. Njirayi imathetsa kulephera kwa kujambula kwachikhalidwe, komwe sikungatheke poyang'ana zinthu zomwe zimayamwa mofooka. Kutulutsa thovu kwa zitsanzozo kunkachitika mkati mwa ng'anjo yopangidwa ndi thovu, yokhala ndi zenera lalikulu la 15 mm x 15 mm loyang'aniridwa ndi njira ya X-ray. Kukula kwachitsanzo, monga momwe tawonetsera mkuyu 3, ndi 15 mm × 15 mm × 2 mm. Chitsanzocho chimayikidwa mu nkhungu yotulutsa thovu yomwe imakhala ndi mapepala angapo a ceramic. Panthawi yonse yotulutsa thovu, ma X-ray amatha kudutsa pachitsanzocho ndipo amajambulidwa ndi kamera yolumikizana ndi charger (CCD). Gwero la X-ray losankhidwa linkagwira ntchito mwamphamvu 20 Kev, ndipo kukula kopitilira muyeso kwa 7.4 mm × 7.4 mm kunagwiritsidwa ntchito kuti athe kuyang'anitsitsa mwatsatanetsatane za momwe thovu lonse limachitira.

Ndikofunikira kudziwa kuti zitsanzo zomwe zawonedwa zidayikidwa m'njira yolunjika kumayendedwe akugudubuzika komanso kuwongolera. Onse otsogolera omwe ali ndi 0.5 wt% Cf ndi omwe alibe 0.5 wt% Cf anali ndi mapepala awo omwe amachotsedwa kumbali zonse za zitsanzo pogwiritsa ntchito EDM. Zotsatira za CF pa mawonekedwe a thovu a aluminiyamu adafufuzidwa. Kuphatikiza apo, zoyambira zokhala ndi zolemba zosiyanasiyana zidathiridwa thovu mung'anjo yotenthetsera yomweyo pa kutentha kokhazikitsidwa kale kwa 620 ◦C.

2.3.3. Kuyeza kwa compression makina katundu

Zitsanzo zoponderezedwazo zinadulidwa mu zitsanzo za cylindrical ndi kutalika kwa 23 mm ndi m'mimba mwake 20 mm ndi EDM, ndipo njira iliyonse inatsimikiziridwa kuti ikhale ndi ma pores osachepera 10 kuti apewe kukula kwake. Mayeso oponderezedwa a Quasi-static adachitidwa motsatira miyezo ya ISO13314-2011 ndi GB/T31930-2015, pogwiritsa ntchito makina oyesa ma elekitironi a AG-XPLUS okhala ndi katundu wokwanira 100 KN. Zitsanzo zitatu zinayesedwa pagulu lililonse, ndipo zokhotakhota za kupsinjika maganizo m'mapepalawa zikuyimira zotsatira zapakati zomwe zimapezedwa kuchokera ku zitsanzo zitatu zoyesedwa. Mayesero onse adachitidwa pansi pa kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe ka kayendetsedwe kake.

Chithunzi 4.Zithunzi zosinthika za synchrotron radiation za Cf/AFS zotulutsa thovu: (a) kalambulabwalo wopanda thovu pa t0 mphindi ya 380 ◦C; (b) - (c) kusungunuka kwa mkuwa wa elemental ndi mtundu wa II nucleation panthawi ya kusungunuka koyambirira; (d)–(g) heterogeneous nucleation ndi kukula njira thovu; ndi (h)–(i) ming’oma kusakanikirana ndi kung’ambika.

3. Zotsatira ndi zokambirana

3.1. In situ thovu khalidwe pansi pa synchrotron radiation

3.1.1. Kusintha kwa thovu kwa Cf/AFS

Chithunzi 4imawonetsa zithunzi zingapo zama radiation ya synchrotron zomwe zikuwonetsa kutulutsa thovu kwa Cf/AFS. Zithunzi zoyambirira za CF/AFS(Chithunzi 4 (a))anagwidwa pamene matrix anali olimba pa 380 ◦ C, ndipo nthawi ino adayikidwa ngati t0. Poyerekeza ndi zigawo zina zomwe zili mu kalambulabwalo, Cf imawoneka yakuda mkati mwa matrix olemera kwambiri a aluminium. Izi zitha kukhala chifukwa cha kuchuluka kwa mkuwa pa fiber pamwamba, monga zikuwonekeraChithunzi 2(c)–(d), yomwe ili ndi kulemera kwakukulu kwa atomiki poyerekeza ndi zigawo zina za kalambulabwalo. Kuphatikiza apo, ambiri a CF amawonedwa kukhala omwazikana komanso olekanitsidwa, m'malo mophatikizana pamodzi, monga momwe zasonyezedwera muChithunzi 4 (a). Izi zikutanthawuza kuti ndi 0.5 wt% kuwonjezera kwa Cf, 3 h kusonkhezera kachitidwe kakhoza kupeza bwino lomwe likufunika kubalalitsidwa.

Pa t0+194s (monga tawonera muChithunzi 4 (b)), tinthu tambiri toyera tozungulira tozungulira tokhala ndi mainchesi kuyambira 90 μm mpaka 180 μm titha kuwonedwa mu matrix otuwa a aluminiyamu (yomwe ili ndi muvi wofiyira). Chiwerengero cha thovu chinapitilira kuwonjezeka mkati mwa 46 s, monga zikuwonetsedwa muChithunzi 4(c). Kuonjezera apo, kusintha kwina kochititsa chidwi komwe kukuchitika mu masanjidwewo ndikuti ming'oma ina yaying'ono imakonda kupanga pamwamba pa Cf ndi kuyambitsa kwa Cu dissolutions (yomwe ili ndi bokosi la madontho ofiira). Chodabwitsa ichi chikhoza kukhala chifukwa cha mtundu wa II nucleation womwe umapezeka mkati mwa mkuwa wokhala ndi ufa. Amavomereza kuti kuwonjezera kwa Cu kumachepetsa kwambiri kutentha kwa ma alloys. Izi zimabweretsa kusungunuka kwapang'onopang'ono pozungulira tinthu tating'ono ta ufa mu kalambulabwalo wa ufa wokhala ndi ufa wamkuwa panthawi yotentha, kutulutsa kuchuluka kwa Al-Si-Mg-Cu quaternary eutectic kusungunuka pa kutentha kochepa. Phula la quaternary eutectic melt pool limakonda kukhala dera lofooka mu alloy ndipo limakonda kukhala ndi nucleation. Chotsatira chake, ming'oma imatha kukhala nyukiliya ndikukula pafupi ndi mkuwa wokutidwa ndi ulusi. Kuphatikiza apo, kagawo kakang'ono kamadzi kamene kali mu matrix pakadali pano kumapangitsa kuti mpweya wochokera pakuwola kwa TiH2 uunjike mosavuta mu matrix a aluminium. Mtundu wachiwiri wa nucleation ukhoza kupeweratu mpweya wochuluka womwe umakakamiza madzi otsika kagawo kakang'ono kagawo kakang'ono ndi kufalitsa ming'alu yamadzimadzi, zomwe zimapangitsa kutaya kwakukulu kwa kuchuluka kwa haidrojeni.

Chithunzi 4(d)amawonetsa thovu poyambilira kukhala nyukiliya ndikukula m'chigawo cha Cf pomwe matrix amasungunuka, ndipo malo omwe amakhalapo amafanana ndi wosanjikiza wokutidwa ndi mkuwa (womwe uli ndi bokosi lamadontho ofiira). Ndizodziwika bwino kuti kuwonjezera magawo achiwiri kumawonjezera kuchuluka kwa malo osakanizika a nucleation, potero kumachepetsa chotchinga champhamvu pakupanga thovu latsopano mkati mwa aloyi kusungunula. Pakadali pano, kuchuluka kwa ma nucleation kumakhudzana ndi gawo lonse la nucleation lamtundu uliwonse pa voliyumu iliyonse. Chifukwa chake, zitha kuwonedwa kuti thovulo limayambira pamalo pomwe minyewa ya kaboni imakhala ndikukula mozungulira kutalika kwa kaboni fiber. Ndi kuwonjezeka kwina kwa gawo losungunuka, mavuvu ambiri atsopano akupitiriza kutulukaChithunzi 4(e)–4(g). Komabe, kuchuluka kwa kuphatikizika kwawoko komanso kuphulika kwa thovulo kumachedwa, kusonyeza kuti thovuli lili ndi kukhazikika kwakukulu. Pa t0 + 426s, kuchuluka kwa thovu kumawonjezeka kwambiri, ndipo

voliyumu yoyambira ikuwonetsa kukulitsa kwakukulu(mku. 4(h)). Kuphatikiza apo, kupezeka kwa kusanganikirana kwa thovu (lomwe lili ndi muvi wofiyira), pomwe tinthu tating'onoting'ono timatengedwa ndi zazikulu chifukwa cha kukhwima kwa Ostwald, ndi njira yosapeŵeka pakusinthika kwa thovu zachitsulo [40]. Kukhwima kumeneku kumapangitsanso kuoneka kwa thovu lalikulu ndi losakhazikika (lolembedwa ndi muvi wofiyira mkati).Chithunzi 4(i)).

Chithunzi 5.Zithunzi zosinthika za nthawi za ndondomeko yotulutsa thovu ya AFS pazigawo zosiyana: (a) chotsogola chosasungunuka pa t0 mphindi ya 380 ◦C; (b) kusungunuka kwa elemental mkuwa ndi mtundu II nucleation pa precursor kusungunuka; (c) ma nucleation ndi kukula kwa thovu; ndi (d)–(f) ming’oma kusakanikirana ndi kung’ambika.

3.1.2. Kusintha kwa thovu kwa AFS

Chithunzi cha 5 chikuwonetsa mndandanda wazithunzi za ma radiation a synchrotron zosonyeza kutulutsa thovu kwa AFS. Zofanana ndi Cf/AFS, chithunzi choyambirira cha kutsatizana kwa ma radiation a synchrotron chinajambulidwa pamene AFS inali mu gawo lolimba pa 380 ◦C (onaniChithunzi 5 (a)). Matrix akatenthedwa pamwamba pa kutentha kwa solidus, tinthu tating'ono toyera timawonekeraChithunzi 5 (b) ndi (c), chifukwa cha kuwonongeka kwa TiH2 ndi kuchitika kwa mtundu wa II nucleation m'dera la Cu-rich. Komabe, chiwerengero cha thovu kwaiye ndi kugawa kachulukidwe muChithunzi 5(c)ndizotsika kwambiri poyerekeza ndiChithunzi 4(c). Izi zikuwonetsa kuti Cf/AFS imapereka njira zambiri zotulutsira mpweya woyambirira panthawi ya nucleation, kuteteza kupangika kwakukulu kwa ming'alu ya aluminiyamu matrix okhala ndi kachigawo kakang'ono kamadzimadzi.

Masamba ochepa a AFS nucleation ndi kuthekera kokulirapo kwa kuwira kwachilendo poyerekeza ndi Cf/AFS zitha kuwonedwa kuchokeraChithunzi 5(d)–(f). Kusinthika kwa thovu la AFS sikokhazikika, ndipo makulidwe ake amawonetsa kusinthasintha kwakukulu chifukwa cha kukhalapo kwa thovu lokhala ndi kukula kwa micrometer ndi thovu lalikulu la millimeter (lomwe lili ndi muvi wofiyira). Komanso, kusakhazikika uku komanso kusakhazikika pamayendedwe oyambilira a nucleation kumatha kubweretsa kusiyana kwakukulu pamapangidwe omaliza a pore ndi zida zamakina pakati pa AFS ndi Cf / AFS.

3.2. Kusanthula kwa macrostructure

Kuti mufufuze kusiyana kwa macroscopic pore morphology ndi pore diameter pakati pa AFS ndi Cf/AFS, masangweji awiri a masangweji adakonzedwa pansi pamikhalidwe ya labotale pa kutentha kwa thovu la 620 ◦C kwa 15 min. Ma macrostructures ndi kukula kwa maselo a AFS ndi Cf/AFS akuwonetsedwa muChithunzi 6. Kuyerekeza kwa magawo oyimirira amitundu iwiri ya masangweji kumawonetsa kuti thovu la Cf/AFS lili ndi ma cell ocheperako komanso zolakwika zochepa monga kusweka kapena kuphatikizana kwa maselo (onaniChithunzi 6 (b)). M'malo mwake, monga zikuwonetsedwa muChithunzi 6 (a), AFS imasonyeza kusauka kwa pore ndi kukhalapo kwa ma pores akuluakulu modabwitsa. Panthawiyi, pore diameter yofanana ya AFS ndi Cf/AFS inali 2.9 ± 0.2 mm ndi 1.9 ± 0.1 mm, motero, kutanthauza kuti m'mimba mwake munali woyengedwanso ndi kuwonjezera kwa Cf (onaniChithunzi 6(c) ndi (d)).

Kusintha kwa mapangidwe a pore kumakhudzidwa ndi njira ziwiri zopikisana: kuwonongeka kwa TiH2 ndi kuphatikiza ndi kuphulika kwa thovu. Kuwonongeka kwa TiH2 kumathandizira kuwonjezeka kwa chiwerengero cha nucleation, porosity, ndi kuwonjezeka kwa mlingo, pamene kuphatikiza ndi kuphulika kwa thovu kumachepetsa chiwerengero cha pores ndikuwonjezera kukula kwa pores. Kuchepetsa kuphatikizika kwa bubble ndi kuphulika kwa zochitika kumathandizira kupeza mawonekedwe abwinoko a ma cell. Chifukwa chake, kukhazikika kwakukulu kwa chithovu ndikofunikira kuti musunge homogeneity ya kapangidwe ka pore panthawi yopanga thovu. Kwa Cf/AFS, kuwonjezera kwa Cf kumathandizira kwambiri kunyowa kwa ulusi ndi kusungunuka kwa aluminiyumu. Mofanana ndi zomwe zinanenedwa kuti CF inalimbikitsa thovu la aluminiyamu [44] yokonzedwa ndi njira yosungunula thovu, kuwonjezera kwa Cf kumapangitsa kuti thovu la aluminiyamu likhale lokhazikika poletsa kuphulika kwa khoma la cell ndi kuchepetsa kusakanikirana. Pakalipano, Cf ikhoza kupanga dongosolo lofanana ndi ukonde mu khoma la selo, lomwe limapanga mphamvu yolekanitsa ndikuletsa kuphulika kwa thovu, motero, kupititsa patsogolo dongosolo la selo, kukhazikika kwa thovu, ndi kufanana kwa kugawa kwa pore.

3.3. Makhalidwe a Microstructural

Chithunzi 7 (a)imasonyeza microstructure ya khoma la selo pambuyo pochita thovu ndi AFS. Monga tafotokozera za AlSi6Cu4Mg4 alloy foams, eutectic Al-Si, Mg2Si, Al2Cu, ndi Al5Cu2Mg8Si6, alipo mu alloy, zomwe zikugwirizana ndi zomwe zapezedwa kuchokera ku kufufuza kwa EDS muChithunzi 7 (b). Magawo opundukawa amachepetsa magwiridwe antchito a thovu la aluminiyamu pofooketsa khoma la pore kapena kukhala ngati gwero la ming'alu panthawi yopindika. Choncho, kupititsa patsogolo makina a khoma la pore kupyolera mwa kuwonjezera magawo olimbikitsa ndi njira yabwino komanso yothandiza.

Kwa Cf/AFS, imatha kuwonedwa kuchokeraChithunzi 7(c) ndi (d)kuti Cf imagawidwa mkati mwa khoma la selo kapena m'mphepete mwa khoma la selo, kusonyeza kuti Cf ili ndi kunyowa kwakukulu ndi kusungunuka kwa aluminiyumu. Kuphatikiza apo, zimawonekera (onaniChithunzi 7(d)) kuti pang'ono pang'onopang'ono gawo la Al2Cu limapanga pa mawonekedwe pakati pa ulusi ndi aluminiyumu kusungunuka. Chodabwitsa ichi chimathandizira kukwaniritsa mgwirizano wamphamvu pakati pa ulusi ndi matrix. Kupitilira kwa kufalikira uku kumatha kuwonedwa mwachidwiChithunzi 4(a)–(c). Zindikirani kuti, gawo la mpweya silimazungulira kwathunthu mpweya wa carbon, ndipo dziko ndi kuchuluka kwa kugawa kumeneku ndizopindulitsa kwa Cf / AFS. Kutengera ndi kafukufuku wa Lv et al, pa Cf yolimbitsa ma aluminium matrix kompositi zida, zidawonetsedwa kuti kuchuluka koyenera kwa gawo locheperako kumatha kukhudza ndikuwongolera mphamvu zomangira zomangira.

Chithunzi 6.Magawo olunjika a chitsanzo choyimira (a) AFS ndi (b) Cf/AFS. Magawo ofananirako ndi magawo agawo ofanana ndi (a) ndi (b) akuwonetsedwa mu (c) ndi (d), motsatana. Mzere wolimba wopitilira mu (c) ndi (d) umayimira kulowa kwanthawi zonse. Regression (R2) imayimira ubwino wokwanira.

Chithunzi 7.Zithunzi za SEM (a) ndi (b) zikuwonetsa ma microstructures ofanana ndiChithunzi 6(a) AFS ndiChithunzi 6(b) CF/AFS, motero,Chithunzi 7(b) ndi (d) kuwonetsa kukwezedwa komweko kwaChithunzi 7(a) ndi (c), motsatira.

3.4. Njira ya CF kukhazikika kwa thovu la Al-Si-Mg-Cu

Kutengera kusanthula komwe kwatchulidwa pamwambapa, chiwonetsero chadongosolo la makina otulutsa thovu a Cf/AFS ndi AFS chikufotokozedwa mwachidule muChithunzi 8. Kusiyana kwakukulu pakati pa Cf/AFS ndi AFS mu gawo la nucleation, kukula kwa thovu, ndi siteji yolumikizana, ndi gawo lolimba pang'onopang'ono, monga momwe zasonyezedwera muChithunzi 8(a) ndi (b).

Chithunzi 8.Chithunzi chojambula cha Cf / AFS ndi khalidwe lotulutsa thovu la AFS: (a) Cf / AFS; ndi (b) AFS.

Mu nucleation siteji ya AlSi6Cu4Mg4 aloyi thovu, thovu amakonda nucleate mkati madzi quaternary eutectic ozungulira mkuwa particles, osati nyukiliya pa malo a TiH2 particles. Mtundu uwu wa nucleation m'dera lofooka kwambiri la kalambulabwalo (mtundu wa II nucleation) umapereka njira zambiri zopulumutsira mpweya wotulutsidwa ndi kuwonongeka kwa TiH2, kupeŵa kudzikundikira kwa mpweya ndikupangitsa ming'alu kufalikira mu aluminium kusungunuka. Kuphatikizika kwa ulusi wa kaboni wokhala ndi mkuwa kumawoneka kuti kumapangitsanso njira zambiri zotulutsira H2. Komabe, popeza kusungunuka kwa aluminiyumu kulibe kagawo kakang'ono kamadzimadzi kamene kamakhalapo panthawiyi, zimakhala zovuta kuti thovu laling'ono ngati limeneli likhale ndi gwero lokwanira la H2 kuti lipitirize kukula. Chotsatira chake, tinthu tating'onoting'ono timeneti timaphulika mkati mwa sungunuka pamene kutentha kumakwera. Pamene chotsatiracho chasungunuka kwathunthu, H2 yotulutsidwa kuchokera ku chiwawa cha dehydrogenation reaction ya TiH2 idzakhala nucleate ndikukula mofulumira kutengera nucleation point. CF imapereka malo ambiri osakanikirana a nucleation kuti apange thovu, zomwe zimawonjezera kuchuluka kwa nucleation. Panthawi imodzimodziyo, kukhalapo kwa Cf kumalepheretsanso kukhudzana ndi kuphatikiza kwa thovu loyamba ndikupewa mapangidwe a thovu lalikulu.

Panthawi ya kukula ndi kuphatikizika kwa thovu, kuwonjezera kwa Cf kumathandizira kwambiri kukhazikika kwa thovu. Chifukwa chake ndi chakuti Cf ndi aluminiyamu zimasungunuka zimakhala bwino kunyowa, ndipo ulusiwo ukhoza kutsekeka mosavuta pakati pa mawonekedwe awiri amadzi a gasi kuti apange maukonde (monga momwe zikuwonetsera muChithunzi 7(c)). Pamene filimu yamadzimadzi imaphwanyidwa, ulusi ukhoza kupanga mphamvu yolekanitsa kuti ikanize kuyamwa kuchokera kumalire a mapiri, motero kulepheretsa filimu yamadzimadzi kuti iwonongeke. Chifukwa chake Cf/AFS imafunikira nthawi yayitali yotulutsa thovu poyerekeza ndi AFS, yokhala ndi kukhazikika kwapamwamba komwe kumatha kusunga mawonekedwe a pore panthawi yakusintha kwa thovu.

Panthawi yolimbitsa pang'onopang'ono, ma thovu mu Cf / AFS sakulanso ndipo ulusi umayikidwa mkati mwa khoma la selo (lomwe lili ndi bokosi la madontho ofiira). Kusungidwa kwa ulusi uku kumalepheretsa kuyamwa kwa thovu laling'ono ndi zazikulu, monga momwe zimawonekera mu Ostwald kusasitsa, ndipo zimalepheretsa kuphulika kwa khoma la cell chifukwa cha kukulitsa kolimba. Zotsatira zake, Cf/AFS imawonetsa mawonekedwe a pore kwambiri komanso zolakwika zochepa poyerekeza ndi AFS.

3.5. Zimango katundu

Ma curve opanikizika a Cf/AFS ndi AFS okhala ndi porosity yofanana (83.2% ndi 81.4%, motsatana) amaperekedwaChithunzi 9 (a). Kupindika kwa kupsinjika-kupanikizika kumawonetsa mawonekedwe a magawo atatu, okhala ndi mzere wosalala, dera lamapiri, ndi chigawo cha densification. Mphamvu zolimbikitsira zokolola za AFS ndi CF/AFS zinali 8.44 MPa ndi 11.87 MPa, motsatana. Kuchuluka kwa zokolola za Cf / AFS kunawonjezeka ndi 40.6% poyerekeza ndi AFS. Pakadali pano, mphamvu yoyamwitsa mphamvu ya Cf/AFS ndiyabwinopo kuposa ya AFS pamavuto omwewo, monga zikuwonetsedwa muChithunzi 9 (b). Mayamwidwe amphamvu a AFS ndi Cf/AFS ndi pafupifupi 3.3 MJ/m3 ndi 6.1 MJ/m3, motsatana. Mphamvu ya mayamwidwe ya mphamvu ya Cf/AFS imakula ndi 84.8% poyerekeza ndi AFS.

Chithunzi 9.Kupanikizika kwapakatikati-ma curve ndi mayamwidwe amphamvu a Cf / AFS ndi AFS: (a) ma curve opsinjika-sitima yapamtunda; (b) mayamwidwe amphamvu zokhotakhota.

Kuphatikizika kwa Cf kunakulitsa kwambiri mawonekedwe amakina a thovu pachimake. Iwo amadziwika kuti makina katundu waaluminium thovuzimagwirizana kwambiri ndi kapangidwe ka pore ndi strut mechanical properties. Kusanthula kwa macrostructural kunawonetsa kuti kuwonjezera kwa Cf kunayeretsa kukula kwa pore, kugawa bwino pore, ndikuchepetsa kuwonongeka kwa pore. Zofanana ndi zomwe Sasikumar et al. ndi Yangetal. pore awiri ang'onoang'ono komanso kugawa pore pang'ono ndizopindulitsa kwambiri kupititsa patsogolo mphamvu zopondereza komanso kuyamwa kwamphamvu. Komanso, zotsatira za microstructure pa makina a thovu makamaka chifukwa cha CF ophatikizidwa mu pore makoma a thovu. Kufalikira ndi kusungunuka kwa mkuwa wokutidwa ndi ulusi wa kaboni mu aluminiyamu matrix kumatha kukwaniritsa mgwirizano wolimba pakati pa ulusi ndi matrix a aluminiyumu, zomwe zimathandizira kutumiza katundu. Mpweya wapamwamba wa carbon modulus wokhazikika pakhoma la pore ukhoza kuchepetsa kusinthika kwa khoma la pore pansi pa kuponderezedwa ndikuwongolera mphamvu yonyamula katundu. Zinthu zonsezi zimakomera Cf/AFS kuti ikwaniritse zokolola zapamwamba komanso mphamvu zoyamwa mphamvu poyerekeza ndi AFS.

4. Mapeto

CF/AFS ndi AFS zidakonzedwa ndi njira yolongedza zitsulo za ufa mu ntchitoyi. Khalidwe lotulutsa thovu la Cf/AFS ndi AFS lidawonedwa mwamphamvu kudzera mu radiation ya synchrotron mpaka

fufuzani mphamvu ya CF pa nucleation ya kuwira ndi kukula. Kuphatikiza apo, Cf pa pore morphology, kugawa pore, ndi kuponderezana kwa thovu za aluminiyamu zidawunikidwa bwino. Mfundo zazikuluzikulu ndi izi:

(1) Zowunikira za Synchrotron mu situ zikuwonetsa kuti zonse za Cf / AFS ndi AFS zotulutsa thovu zimawonetsa magawo atatu osiyana: kuphulika kwa nucleation, kukula kwa kuwira ndi kuphatikiza, ndi kulimba.

Poyerekeza ndi AFS, kutulutsa thovu kwa Cf/AFS kumawonetsa kukhazikika kwapamwamba komanso kufanana kwa kuwira. AFS imakonda kupanga pores zazikulu kwambiri komanso zowoneka bwino panthawi yakusintha kwa pore. Kuphatikiza apo, kusagwirizanaku kumabwera chifukwa cha kuchuluka kwa nucleation ya Cf, yomwe imalepheretsa kuphulika kwa khoma ndikuchepetsa kuphatikizika ndikuwonjezera kuchuluka kwa nucleation.

(2) Kuphatikizika kwa 0.5 wt.% Cf kumayeretsa pore yofanana kuchokera ku 2.9 ± 0.2 mm mpaka 1.9 ± 0.1 mm, kuchepetsa kwambiri zolakwika za pore. Panthawi imodzimodziyo, microstructure imasonyeza kunyowa kwabwino kwa Cf, komwe kumagawidwa pakhoma la pore ndi mawonekedwe olimba a gasi, motero kumapangitsa kuti chithovu chikhale chokhazikika.

(3) Poyerekeza ndi AFS, mphamvu zowonjezera zokolola ndi mphamvu zowonongeka za Cf / AFS zinawonjezeka pafupifupi 40.6% ndi 84.8%, motero. Zomwe zapeza pa kafukufukuyu zitha kupereka malingaliro olimbikitsa ma sangweji a aluminiyamu a thovu okhala ndi zitsulo zolumikizana ndi zitsulo zomwe zimatha kugwiritsa ntchito uinjiniya m'mafakitale oyendetsa magalimoto ndi ndege.

Nkhani yochokera ku Journal of Materials Research and Technology