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Ma biofilms ndi gawo lofunikira kwambiri pakukula kwa matenda osatha, makamaka pamene zipangizo zachipatala zikukhudzidwa. Vutoli limabweretsa vuto lalikulu kwa madokotala, chifukwa maantibayotiki wamba amatha kuchotseratu ma biofilms pang'ono chabe. Kuletsa kupangika kwa biofilm kwapangitsa kuti pakhale njira zosiyanasiyana zokutira ndi zinthu zatsopano. Njirazi cholinga chake ndi kuphimba pamwamba mwanjira yolepheretsa kupangika kwa biofilm. Ma alloys achitsulo, makamaka omwe ali ndi zitsulo zamkuwa ndi titaniyamu, apezeka ngati zokutira zabwino kwambiri zophera maantibayotiki. Nthawi yomweyo, kugwiritsa ntchito ukadaulo wopopera wozizira kwawonjezeka chifukwa ndi njira yoyenera yogwiritsira ntchito zinthu zomwe zimakhudzidwa ndi kutentha. Gawo la cholinga cha kafukufukuyu linali kupanga galasi latsopano lachitsulo lopangidwa ndi ternary Cu-Zr-Ni pogwiritsa ntchito njira zopangira makina. Ufa wozungulira womwe umapanga chinthu chomaliza umagwiritsidwa ntchito ngati zopangira zokutira zozizira za chitsulo chosapanga dzimbiri pa kutentha kochepa. Ma substrates okutidwa ndi galasi lachitsulo adatha kuchepetsa kwambiri kupangika kwa biofilm ndi chipika chimodzi poyerekeza ndi chitsulo chosapanga dzimbiri.
M'mbiri yonse ya anthu, anthu onse akhala akupanga ndi kulimbikitsa kuyambitsa zipangizo zatsopano zomwe zikugwirizana ndi zofunikira zake, zomwe zapangitsa kuti zinthu ziyende bwino komanso kuti zinthu ziyende bwino padziko lonse lapansi. 1. Nthawi zonse zakhala zikunenedwa kuti anthu amatha kupanga zipangizo ndi zida zopangira zinthu ndi mapangidwe opangira zinthu ndi kufotokozera zinthu kuti apeze phindu mu thanzi, maphunziro, mafakitale, zachuma, chikhalidwe ndi madera ena kuchokera kudziko lina kapena dera lina kupita ku lina. 2 Kwa zaka 60, asayansi a zipangizo akhala akugwiritsa ntchito nthawi yawo yambiri kuyang'ana kwambiri pa chinthu chimodzi chachikulu: kufunafuna zipangizo zatsopano komanso zamakono. Kafukufuku waposachedwapa wayang'ana kwambiri pakukweza ubwino ndi magwiridwe antchito a zipangizo zomwe zilipo, komanso kupanga ndi kupanga mitundu yatsopano ya zipangizo.
Kuwonjezera zinthu zophatikiza, kusintha kwa kapangidwe kake ka zinthu, komanso kugwiritsa ntchito njira zotenthetsera, makina kapena thermo-mechanical processing kwapangitsa kuti zinthu zosiyanasiyana zisinthe kwambiri. Kuphatikiza apo, mankhwala omwe sanamvekepo mpaka pano apangidwa bwino. Kuyesetsa kosalekeza kumeneku kwapanga banja latsopano la zinthu zatsopano, zomwe zimadziwika kuti Advanced Materials2. Makristalo, nanoparticles, nanotubes, quantum dots, zero-dimensional, amorphous metallic glasses, ndi high-entropy alloys ndi zitsanzo chabe za zinthu zapamwamba zomwe zayambitsidwa padziko lapansi kuyambira pakati pa zaka za m'ma 1900. Pakupanga ndikupanga ma alloys atsopano okhala ndi makhalidwe abwino, kaya mu chinthu chomaliza kapena m'magawo apakati opanga, vuto la kusalingana nthawi zambiri limawonjezeredwa. Chifukwa chokhazikitsa njira zatsopano zopangira kuti zisiyane kwambiri ndi equilibrium, gulu latsopano la ma alloys okhazikika, otchedwa metallic glasses, lapezeka.
Ntchito yake ku Caltech mu 1960 inabweretsa kusintha kwakukulu mu lingaliro la zitsulo zosungunuka pamene anapanga zitsulo zosungunuka za Au-25 at.% Si mwa kupanga madzi mofulumira pa madigiri pafupifupi miliyoni pa sekondi. 4. Chochitika cha Pulofesa Pol Duwezs sichinangolengeza chiyambi cha mbiri ya magalasi achitsulo (MG), komanso chinapangitsa kusintha kwa momwe anthu amaganizira za zitsulo zosungunuka. Kuyambira pamene maphunziro oyambirira a kupanga zitsulo zosungunuka za MG, magalasi pafupifupi onse achitsulo apangidwa kwathunthu pogwiritsa ntchito njira imodzi mwa izi: (i) kulimba mofulumira kwa kusungunuka kapena nthunzi, (ii) kusokonezeka kwa atomiki kwa lattice, (iii) machitidwe a solid-state amorphization pakati pa zinthu zoyera zachitsulo, ndi (iv) kusintha kwa solid-state kwa magawo okhazikika.
Ma MG amadziwika ndi kusowa kwa dongosolo la atomiki lakutali logwirizana ndi makhiristo, lomwe ndi khalidwe lodziwika bwino la makhiristo. M'dziko lamakono, kupita patsogolo kwakukulu kwachitika m'munda wa galasi lachitsulo. Ndi zipangizo zatsopano zokhala ndi zinthu zosangalatsa zomwe sizimangofunika mu fizikisi ya boma lolimba, komanso mu metallurgy, chemistry pamwamba, ukadaulo, biology ndi madera ena ambiri. Mtundu watsopanowu wa zinthu umasonyeza zinthu zosiyana ndi zitsulo zolimba, zomwe zimapangitsa kuti zikhale zosangalatsa kugwiritsa ntchito ukadaulo m'magawo osiyanasiyana. Ali ndi zinthu zina zofunika; (i) kusinthasintha kwakukulu kwa makina ndi mphamvu yotulutsa, (ii) kupendekera kwakukulu kwa maginito, (iii) kukakamiza kochepa, (iv) kukana dzimbiri kosazolowereka, (v) kudziyimira pawokha kutentha Kuyendetsa kwa 6,7.
Kusakaniza kwa makina (MA)1,8 ndi njira yatsopano, yomwe idayambitsidwa koyamba mu 19839 ndi Pulofesa CC Kock ndi anzake. Anapanga ufa wa Ni60Nb40 wosasinthika popera chisakanizo cha zinthu zoyera pa kutentha kozungulira komwe kuli pafupi kwambiri ndi kutentha kwa chipinda. Kawirikawiri, MA reaction imachitika pakati pa kusakanikirana kwa ufa wa reactant mu reactor, nthawi zambiri wopangidwa ndi chitsulo chosapanga dzimbiri kupita ku mpira mill 10 (Chithunzi 1a, b). Kuyambira pamenepo, njira iyi yogwirira ntchito yolimba yakhala ikugwiritsidwa ntchito pokonzekera ufa watsopano wa aloyi wagalasi wosasinthika/wachitsulo pogwiritsa ntchito mill yotsika (Chithunzi 1c) ndi mill yamphamvu kwambiri, komanso mill ya ndodo11,12,13,14,15, 16. Makamaka, njira iyi yakhala ikugwiritsidwa ntchito pokonzekera machitidwe osasinthika monga Cu-Ta17, komanso ma alloys okwera kwambiri monga Al-transition metal systems (TM; Zr, Hf, Nb ndi Ta)18,19 ndi Fe-W20, omwe sangapezeke pogwiritsa ntchito njira zokonzekera zachikhalidwe. Kuphatikiza apo, MA imaonedwa kuti ndi imodzi mwa zida zamphamvu kwambiri za nanotechnology pokonzekera tinthu ta nanocrystalline ndi nanocomposite powder particles za metal oxides, carbides, nitrides, hydrides, carbon nanotubes, nanodiamonds, komanso kukhazikika kwakukulu kudzera mu njira yoyamba yoyambira pamwamba ndi magawo okhazikika.
Chithunzi chosonyeza njira yopangira yomwe imagwiritsidwa ntchito pokonzekera chophimba cha Cu50(Zr50−xNix) chagalasi lachitsulo (MG)/SUS 304 mu kafukufukuyu.(a) Kukonzekera ufa wa MG alloy wokhala ndi kuchuluka kosiyana kwa Ni x (x; 10, 20, 30 ndi 40 at.%) pogwiritsa ntchito njira yopukusira mpira wopanda mphamvu zambiri.(a) Zipangizo zoyambira zimayikidwa mu silinda ya zida pamodzi ndi mipira yachitsulo ya zida, ndipo (b) zimatsekedwa mu bokosi la magolovesi lodzazidwa ndi mpweya wa He.(c) Chitsanzo chowonekera cha chopukusira chomwe chikuwonetsa kayendedwe ka mpira panthawi yopukusira. Chomaliza cha ufa chomwe chinapezedwa patatha maola 50 chinagwiritsidwa ntchito kuphimba gawo la SUS 304 pogwiritsa ntchito njira yozizira yopopera (d).
Ponena za malo opangidwa ndi zinthu zambiri (substrates), uinjiniya wa pamwamba umaphatikizapo kupanga ndi kusintha malo (substrates) kuti apereke makhalidwe enaake akuthupi, a mankhwala ndi aukadaulo omwe sali muzinthu zoyambirira. Makhalidwe ena omwe angawongoleredwe bwino ndi mankhwala a pamwamba ndi monga kukana kukhuthala, kukana kukhuthala ndi dzimbiri, kukana kukhuthala, kusagwirizana kwa zinthu, mphamvu zamagetsi, ndi kutchinjiriza kutentha, kungotchulapo zochepa. Ubwino wa pamwamba ukhoza kusinthidwa pogwiritsa ntchito njira zachitsulo, zamakina kapena za mankhwala. Monga njira yodziwika bwino, chophimba chimangotanthauzidwa ngati gawo limodzi kapena angapo azinthu zomwe zimayikidwa pamwamba pa chinthu chopangidwa ndi zinthu zina. Chifukwa chake, chophimbacho chimagwiritsidwa ntchito pang'ono kuti chikwaniritse zinthu zina zaukadaulo kapena zokongoletsera zomwe zimafunidwa, komanso kuteteza zipangizo ku kuyanjana kwa mankhwala ndi zakuthupi komwe kumayembekezeredwa ndi chilengedwe chozungulira23.
Pofuna kuyika zigawo zoyenera zotetezera pamwamba ndi makulidwe kuyambira ma micrometer ochepa (osakwana ma micrometer 10-20) mpaka ma micrometer opitilira 30 kapena ma millimeter ochepa, njira ndi njira zambiri zitha kugwiritsidwa ntchito. Kawirikawiri, njira zophikira zitha kugawidwa m'magulu awiri: (i) njira zophikira zonyowa, kuphatikiza electroplating, electroless plating, ndi hot-dip galvanizing methods, ndi (ii) njira zophikira zouma, kuphatikiza brazing, surfacing, physical vapor deposition (PVD), chemical vapor deposition (CVD), thermal spray techniques ndi cold spray techniques 24 (Chithunzi 1d).
Ma biofilm amatanthauzidwa ngati magulu a tizilombo toyambitsa matenda omwe amalumikizidwa mosasinthika pamwamba ndipo amazunguliridwa ndi ma polima opangidwa okha (EPS). Kupangika kwa biofilm yokhwima pamwamba kungayambitse kutayika kwakukulu m'magawo ambiri amafakitale, kuphatikiza mafakitale azakudya, machitidwe amadzi, ndi malo azaumoyo. Mwa anthu, pamene biofilm ipangidwa, matenda opitilira 80% a tizilombo toyambitsa matenda (kuphatikiza Enterobacteriaceae ndi Staphylococci) ndi ovuta kuchiza. Kuphatikiza apo, biofilm yokhwima yanenedwa kuti ndi yolimba kwambiri ku chithandizo cha maantibayotiki poyerekeza ndi maselo a planktonic bacterial, zomwe zimaonedwa ngati vuto lalikulu la chithandizo. Zipangizo zophimba pamwamba za antimicrobial zochokera ku mankhwala achilengedwe zakhala zikugwiritsidwa ntchito m'mbuyomu. Ngakhale kuti zinthu zotere nthawi zambiri zimakhala ndi zinthu zoopsa zomwe zingakhale zoopsa kwa anthu,25,26 zingathandize kupewa kufalikira kwa mabakiteriya ndi kuwonongeka kwa zinthu.
Kukana kwa mabakiteriya ku mankhwala opha tizilombo toyambitsa matenda chifukwa cha kapangidwe ka biofilm kwapangitsa kuti pakhale kufunika kopanga malo opha tizilombo toyambitsa matenda omwe angagwiritsidwe ntchito mosamala27. Kupanga malo opha tizilombo toyambitsa matenda kapena mankhwala omwe amaletsa mabakiteriya kumanga ndi kupanga biofilms chifukwa chomatira ndi njira yoyamba mu njirayi27. Ukadaulo wachiwiri ndikupanga zokutira zomwe zimathandiza kuti mankhwala opha tizilombo toyambitsa matenda aperekedwe komwe akufunikira, mozama kwambiri komanso mokonzedwa bwino. Izi zimachitika popanga zinthu zapadera monga graphene/germanium28, black diamond29 ndi ZnO-doped diamond-like carbon coatings30 zomwe zimalimbana ndi mabakiteriya, ukadaulo womwe umakulitsa poizoni ndi chitukuko cha kukana chifukwa cha kapangidwe ka biofilm umachepetsedwa kwambiri. Kuphatikiza apo, zokutira zomwe zimaphatikizapo mankhwala opha tizilombo m'malo kuti atetezedwe kwa nthawi yayitali ku kuipitsidwa ndi mabakiteriya zikutchuka kwambiri. Ngakhale njira zonse zitatuzi zimatha kupanga zotsatira zopha tizilombo pamalo ophimbidwa, iliyonse ili ndi zoletsa zake zomwe ziyenera kuganiziridwa popanga njira zogwiritsira ntchito.
Zogulitsa zomwe zili pamsika pano zikulepheretsedwa ndi nthawi yokwanira yowunikira ndikuyesa zophimba zoteteza kuti zipeze zosakaniza zomwe zimagwira ntchito m'thupi. Makampani amanena kuti zinthu zawo zidzapatsa ogwiritsa ntchito zinthu zofunika kwambiri; Komabe, izi zakhala chopinga pa kupambana kwa zinthu zomwe zili pamsika. Zosakaniza zochokera ku siliva zimagwiritsidwa ntchito mu mankhwala ambiri ophera tizilombo toyambitsa matenda omwe alipo kwa ogula. Zogulitsazi zimapangidwa kuti ziteteze ogwiritsa ntchito ku zotsatira zoopsa za tizilombo toyambitsa matenda. Kuchedwa kwa mphamvu ya maantibayotiki komanso poizoni wokhudzana ndi mankhwala a siliva kumawonjezera kukakamiza kwa ofufuza kuti apange njira ina yosavulaza36,37. Kupanga chophimba cha maantibayotiki padziko lonse chomwe chimagwira ntchito mkati ndi kunja kukuonekabe kukhala ntchito yovuta. Izi zili choncho chifukwa cha zoopsa zomwe zimagwirizana nazo pa thanzi ndi chitetezo. Kupeza mankhwala ophera tizilombo omwe sakhala oopsa kwa anthu ndikupeza momwe angawaphatikizire mu zinthu zophikira zomwe zimakhala ndi moyo wautali ndi cholinga chomwe chimafunidwa kwambiri38. Zipangizo zamakono zophera tizilombo toyambitsa matenda komanso zotsutsana ndi biofilm zimapangidwa kuti ziphe mabakiteriya pafupi, kaya kudzera mu kukhudzana mwachindunji kapena pambuyo poti mankhwala ogwiritsira ntchito atulutsidwa. Angathe kuchita izi poletsa kumatirira koyamba kwa mabakiteriya (kuphatikizapo kuthana ndi mapangidwe a mapuloteni pamwamba) kapena kupha mabakiteriya posokoneza khoma la selo.
Kwenikweni, kuphimba pamwamba ndi njira yoyika gawo lina pamwamba pa gawo kuti liwonjezere makhalidwe okhudzana ndi pamwamba. Cholinga cha kuphimba pamwamba ndikusintha kapangidwe kake ndi/kapena kapangidwe ka dera lapafupi ndi pamwamba la gawolo39. Njira zophimba pamwamba zitha kugawidwa m'njira zosiyanasiyana, zomwe zafotokozedwa mwachidule mu Chithunzi 2a. Zophimba zimatha kugawidwa m'magulu otentha, mankhwala, zakuthupi, ndi zamagetsi, kutengera njira yomwe imagwiritsidwa ntchito popanga chophimbacho.
(a) Chithunzi chamkati chomwe chikuwonetsa njira zazikulu zopangira zomwe zimagwiritsidwa ntchito pamwamba pake, ndi (b) zabwino ndi zoyipa zomwe zasankhidwa za njira yozizira yopopera.
Ukadaulo wopopera wozizira umafanana kwambiri ndi njira zachikhalidwe zopopera kutentha. Komabe, palinso zinthu zina zofunika kwambiri zomwe zimapangitsa kuti njira yopopera yozizira ndi zipangizo zopopera zozizira zikhale zapadera kwambiri. Ukadaulo wopopera wozizira ukadalipo, koma uli ndi tsogolo labwino. Mu ntchito zina, zinthu zapadera za kupopera kozizira zimapereka ubwino waukulu, kugonjetsa zofooka za njira zachikhalidwe zopopera kutentha. Zimapereka njira yogonjetsera zofooka zazikulu za ukadaulo wachikhalidwe wopopera kutentha, pomwe ufa uyenera kusungunuka kuti ulowe pansi. Mwachiwonekere, njira yopopera yachikhalidweyi siyoyenera zinthu zomwe zimakhudzidwa kwambiri ndi kutentha monga ma nanocrystals, nanoparticles, magalasi a amorphous ndi achitsulo40, 41, 42. Kuphatikiza apo, zipangizo zopopera kutentha nthawi zonse zimakhala ndi porosity yambiri ndi ma oxides. Ukadaulo wopopera wozizira uli ndi zabwino zambiri kuposa ukadaulo wopopera kutentha, monga (i) kutentha kochepa komwe kumalowa pansi, (ii) kusinthasintha pakusankha zopopera za substrate, (iii) kusakhalapo kwa kusintha kwa gawo ndi kukula kwa tirigu, (iv) mphamvu yayikulu yolumikizana1,39 (Chithunzi 2b). Kuphatikiza apo, zipangizo zopopera zozizira zimakhala ndi kukana dzimbiri kwambiri, mphamvu ndi kuuma kwambiri, mphamvu zamagetsi zambiri komanso kuchuluka kwamphamvu41. Mosiyana ndi ubwino wa njira yozizira yopopera, palinso zovuta zina zogwiritsira ntchito njira imeneyi, monga momwe zasonyezedwera pa Chithunzi 2b. Mukapaka ufa wa ceramic wokha monga Al2O3, TiO2, ZrO2, WC, ndi zina zotero, njira yozizira yopopera singagwiritsidwe ntchito. Kumbali inayi, ufa wa ceramic/chitsulo wophatikizika ungagwiritsidwe ntchito ngati zopangira zokutira. Momwemonso ndi njira zina zopopera kutentha. Malo ovuta komanso malo amkati mwa mapaipi akadali ovuta kupopera.
Popeza ntchito yomwe ikuchitika pano ikufuna kugwiritsa ntchito ufa wachitsulo ngati galasi ngati zinthu zopangira utoto, n'zoonekeratu kuti kupopera mankhwala kwachikhalidwe sikungagwiritsidwe ntchito pa izi. Izi zili choncho chifukwa ufa wachitsulo ngati galasi umasungunuka kutentha kwambiri.
Zida zambiri zomwe zimagwiritsidwa ntchito m'mafakitale azachipatala ndi chakudya zimapangidwa ndi zitsulo zosapanga dzimbiri za austenitic (SUS316 ndi SUS304) zokhala ndi chromium pakati pa 12 ndi 20 wt% popanga zida zopangira opaleshoni. Kawirikawiri zimavomerezedwa kuti kugwiritsa ntchito chromium metal ngati chinthu chophatikiza mu zitsulo zosakaniza kumatha kusintha kwambiri kukana dzimbiri kwa zitsulo zokhazikika. Zitsulo zosapanga dzimbiri, ngakhale kuti zimakana dzimbiri kwambiri, siziwonetsa mphamvu zazikulu zotsutsana ndi tizilombo toyambitsa matenda38,39. Izi zimasiyana ndi kukana kwawo dzimbiri kwambiri. Pambuyo pake, chitukuko cha matenda ndi kutupa chikhoza kunenedweratu, chomwe chimayambitsidwa makamaka ndi kumatirira kwa mabakiteriya ndi kulowa m'malo mwa zinthu zosapanga dzimbiri za biomaterials. Mavuto akuluakulu angabuke chifukwa cha zovuta zazikulu zokhudzana ndi kumatirira kwa mabakiteriya ndi njira zopangira biofilm, zomwe zingayambitse kuwonongeka kwa thanzi, zomwe zingakhale ndi zotsatira zambiri zomwe zingakhudze mwachindunji kapena mwanjira ina thanzi la anthu.
Kafukufukuyu ndi gawo loyamba la pulojekiti yothandizidwa ndi Kuwait Foundation for the Advancement of Science (KFAS), Contract No. 2010-550401, kuti ifufuze kuthekera kopanga ufa wa ternary wa Cu-Zr-Ni wachitsulo pogwiritsa ntchito ukadaulo wa MA (Table 1) popanga chophimba choteteza pamwamba pa filimu yotsutsana ndi mabakiteriya/SUS304. Gawo lachiwiri la pulojekitiyi, lomwe liyenera kuyamba mu Januwale 2023, lidzafufuza mwatsatanetsatane za electrochemical corrosion ndi mawonekedwe a makina a dongosololi. Mayeso atsatanetsatane a microbiological adzachitika pa mitundu yosiyanasiyana ya mabakiteriya.
Mu pepalali, zotsatira za kuchuluka kwa Zr alloying element pa mphamvu yopanga magalasi (GFA) zikukambidwa kutengera mawonekedwe ndi kapangidwe kake. Kuphatikiza apo, mphamvu zotsutsana ndi mabakiteriya za utoto wa galasi lachitsulo / SUS304 composite wokutidwa nazonso zidakambidwa. Kuphatikiza apo, ntchito yomwe ilipo pano yachitika kuti ifufuze kuthekera kwa kusintha kwa kapangidwe ka ufa wa galasi lachitsulo komwe kumachitika panthawi yopopera madzi ozizira mkati mwa dera lamadzi ozizira la makina opangidwa ndi magalasi achitsulo. Monga zitsanzo zoyimira, ma alloy a galasi achitsulo a Cu50Zr30Ni20 ndi Cu50Zr20Ni30 agwiritsidwa ntchito mu kafukufukuyu.
Mu gawoli, kusintha kwa mawonekedwe a ufa wa Cu, Zr ndi Ni mu milling ya mpira wopanda mphamvu zambiri kwaperekedwa. Monga zitsanzo zowonetsera, machitidwe awiri osiyana omwe ali ndi Cu50Zr20Ni30 ndi Cu50Zr40Ni10 adzagwiritsidwa ntchito ngati zitsanzo zoyimira. Njira ya MA ikhoza kugawidwa m'magawo atatu osiyana, monga momwe zasonyezedwera ndi mawonekedwe a metallographic a ufa wopangidwa panthawi yopera (Chithunzi 3).
Makhalidwe a metallographic a ufa wa makina opangidwa ndi alloy (MA) omwe amapezeka pambuyo pa magawo osiyanasiyana a nthawi yopukutira mpira. Zithunzi za electron scanning electron microscopy (FE-SEM) za ufa wa MA ndi Cu50Zr40Ni10 zomwe zimapezeka pambuyo pa nthawi yopukutira mpira ya maola 3, 12 ndi 50 zikuwonetsedwa mu (a), (c) ndi (e) ya dongosolo la Cu50Zr20Ni30, pomwe mu MA yomweyo Zithunzi zofanana za dongosolo la Cu50Zr40Ni10 zomwe zatengedwa pambuyo pa nthawi zikuwonetsedwa mu (b), (d) ndi (f).
Pakugaya mipira, mphamvu yogwira ntchito ya kinetic yomwe ingasamutsidwire ku ufa wachitsulo imakhudzidwa ndi kuphatikiza kwa magawo, monga momwe zasonyezedwera pa Chithunzi 1a. Izi zikuphatikizapo kugundana pakati pa mipira ndi ufa, kumeta kwa ufa womangika pakati kapena pakati pa zopukutira, kukhudzidwa kwa mipira yogwa, kumeta ndi kuwonongeka chifukwa cha kukoka kwa ufa pakati pa zopukutira mipira zoyenda, ndi mafunde ogwedezeka omwe amadutsa Mipira yogwa imafalikira kudzera mu zokolola (Chithunzi 1a). Ufa wa elemental Cu, Zr, ndi Ni unasokonekera kwambiri chifukwa cha kuwotcherera kozizira kumayambiriro kwa MA (maola 3), zomwe zimapangitsa kuti tinthu tating'onoting'ono ta ufa (>1 mm m'mimba mwake). Tinthu tating'onoting'ono tating'onoting'ono tating'onoting'ono timeneti timadziwika ndi kupanga zigawo zokhuthala za zinthu zosakaniza (Cu, Zr, Ni), monga momwe zasonyezedwera pa Chithunzi 3a, b. Kuonjezera nthawi ya MA kufika pa maola 12 (gawo lapakati) kunapangitsa kuti mphamvu ya kinetic ya mphero ya mpira iwonjezereke, zomwe zinapangitsa kuti ufa wophatikizana uwonongeke kukhala ufa wosalala (wosakwana 200 µm), monga momwe zasonyezedwera pa Chithunzi 3c, d. Pa izi Pa siteji, mphamvu yokakamizika yogwiritsidwa ntchito imabweretsa kupangidwa kwa pamwamba pachitsulo chatsopano chokhala ndi zigawo zazing'ono za Cu, Zr, Ni, monga momwe zasonyezedwera pa Chithunzi 3c, d. Chifukwa cha kukonzanso kwa zigawo, zochitika zolimba zimachitika pamalo olumikizirana a flakes kuti apange magawo atsopano.
Pachimake pa njira ya MA (pambuyo pa maola 50), metallography yophwanyika inkaoneka pang'ono chabe (Chithunzi 3e,f), koma pamwamba popukutidwa pa ufawo panali mirror metallography. Izi zikutanthauza kuti njira ya MA yatha ndipo kupangidwa kwa gawo limodzi la reaction kwachitika. Kapangidwe ka zigawo zomwe zalembedwa mu Chithunzi 3e (I, II, III), f, v, vi) kunadziwika pogwiritsa ntchito field emission scanning electron microscopy (FE-SEM) pamodzi ndi energy dispersive X-ray spectroscopy (EDS) (IV).
Mu Table 2, kuchuluka kwa zinthu zophatikizika kwa alloying kumawonetsedwa ngati peresenti ya kulemera konse kwa dera lililonse lomwe lasankhidwa mu Chithunzi 3e, f. Poyerekeza zotsatirazi ndi zinthu zoyambira za Cu50Zr20Ni30 ndi Cu50Zr40Ni10 zomwe zalembedwa mu Table 1, zitha kuwoneka kuti zinthu ziwiri zomalizazi zili ndi zofanana kwambiri ndi zinthu zophatikizika. Kuphatikiza apo, mitengo yogwirizana ya zigawo zomwe zalembedwa mu Chithunzi 3e, f sizitanthauza kuwonongeka kwakukulu kapena kusinthasintha kwa kapangidwe ka chitsanzo chilichonse kuchokera kudera lina kupita ku lina. Izi zikuwonetsedwa ndi mfundo yakuti palibe kusintha kwa kapangidwe kuchokera kudera lina kupita ku lina. Izi zikusonyeza kupanga ufa wa alloy wofanana, monga momwe zasonyezedwera mu Table 2.
Ma micrograph a FE-SEM a ufa womaliza wa Cu50(Zr50−xNix) adapezeka pambuyo pa nthawi 50 za MA, monga momwe zasonyezedwera pa Chithunzi 4a–d, pomwe x ndi 10, 20, 30 ndi 40 pa.%, motsatana. Pambuyo pa gawo ili logaya, ufa umasonkhana chifukwa cha mphamvu ya van der Waals, zomwe zimapangitsa kuti pakhale magulu akuluakulu okhala ndi tinthu tating'onoting'ono tomwe tili ndi mainchesi kuyambira 73 mpaka 126 nm, monga momwe zasonyezedwera pa Chithunzi 4.
Makhalidwe a ufa wa Cu50(Zr50−xNix) womwe wapezeka patatha nthawi ya MA ya maola 50. Pa machitidwe a Cu50Zr40Ni10, Cu50Zr30Ni20, Cu50Zr20Ni30, Cu50Zr10Ni40, zithunzi za FE-SEM za ufa womwe wapezeka patatha nthawi ya MA 50 zikuwonetsedwa mu (a), (b), (c) ndi (d), motsatana.
Asanalowetse ufawo mu chopopera choziziritsa, poyamba ankaunikiridwa mu ethanol yowunikira kwa mphindi 15 kenako nkuumitsa pa 150°C kwa maola awiri. Gawoli liyenera kutengedwa kuti lithane bwino ndi agglomeration yomwe nthawi zambiri imayambitsa mavuto ambiri panthawi yonse yopaka utoto. Pambuyo poti njira ya MA yatha, zizindikiro zina zinachitidwa kuti afufuze kufanana kwa ufa wa alloy. Chithunzi 5a–d chikuwonetsa ma micrograph a FE-SEM ndi zithunzi zofanana za EDS za Cu, Zr ndi Ni alloying elements za Cu50Zr30Ni20 alloy zomwe zapezeka patatha maola 50 a nthawi ya M, motsatana. Tiyenera kudziwa kuti ufa wa alloy womwe umapangidwa pambuyo pa sitepe iyi ndi wofanana chifukwa suwonetsa kusinthasintha kulikonse kwa kapangidwe kupitirira mulingo wa sub-nanometer, monga momwe zasonyezedwera pa Chithunzi 5.
Kapangidwe kake ndi kugawa kwa ufa wa MG Cu50Zr30Ni20 komwe kumapezeka pambuyo pa nthawi 50 za MA ndi FE-SEM/energy dispersive X-ray spectroscopy (EDS).(a) Kujambula zithunzi za SEM ndi X-ray EDS za (b) Cu-Kα, (c) Zr-Lα ndi (d) Ni-Kα.
Mapangidwe a XRD a ufa wa Cu50Zr40Ni10, Cu50Zr30Ni20, Cu50Zr20Ni30 ndi Cu50Zr20Ni30 wopangidwa ndi makina omwe amapezeka pambuyo pa nthawi ya MA ya maola 50 akuwonetsedwa mu Chithunzi 6a–d, motsatana. Pambuyo pa gawo ili la kugaya, zitsanzo zonse zokhala ndi kuchuluka kosiyana kwa Zr zinawonetsa kapangidwe kopanda mawonekedwe ndi mawonekedwe a halo diffusion omwe akuwonetsedwa mu Chithunzi 6.
Mapangidwe a XRD a (a) Cu50Zr40Ni10, (b) Cu50Zr30Ni20, (c) Cu50Zr20Ni30 ndi (d) Cu50Zr20Ni30 ufa pambuyo pa nthawi ya MA ya maola 50. Zitsanzo zonse popanda kupatulapo zinawonetsa mawonekedwe a halo diffusion, zomwe zikutanthauza kupangika kwa gawo lopanda mawonekedwe.
Microscopy ya ma elekitironi yotulutsa mpweya wochuluka (FE-HRTEM) idagwiritsidwa ntchito kuwona kusintha kwa kapangidwe kake ndikumvetsetsa kapangidwe kake ka ufa komwe kumachitika chifukwa cha kugayidwa kwa mpira nthawi zosiyanasiyana za MA. Zithunzi za FE-HRTEM za ufa womwe udapezeka pambuyo pa magawo oyambirira (maola 6) ndi apakati (maola 18) a ufa wa Cu50Zr30Ni20 ndi Cu50Zr40Ni10 zikuwonetsedwa mu Chithunzi 7a, c, motsatana. Malinga ndi chithunzi chowala chamunda (BFI) cha ufa womwe udapangidwa pambuyo pa MA​ maola 6, ufawo umapangidwa ndi tinthu tating'onoting'ono tomwe tili ndi malire omveka bwino a zinthu za fcc-Cu, hcp-Zr ndi fcc-Ni, ndipo palibe chizindikiro chakuti gawo la reaction lapangidwa, monga momwe zasonyezedwera mu Chithunzi 7a. Kuphatikiza apo, mawonekedwe osankhidwa a dera losakanikirana (SADP) otengedwa kuchokera kudera lapakati la (a) adawonetsa mawonekedwe a cusp diffraction (Chithunzi 7b), kusonyeza kukhalapo kwa ma crystallites akulu ndi kusowa kwa gawo losinthika.
Kufotokozera kapangidwe kake ka ufa wa MA komwe kamapezeka pambuyo pa magawo oyambirira (maola 6) ndi apakati (maola 18).(a) Microscopy ya ma elekitironi yotulutsa mpweya wochuluka (FE-HRTEM), ndi (b) mawonekedwe ofananira a dera losakanikirana (SADP) la ufa wa Cu50Zr30Ni20 pambuyo pa chithandizo cha MA kwa maola 6. Chithunzi cha FE-HRTEM cha Cu50Zr40Ni10 chomwe chapezeka pambuyo pa nthawi ya MA ya maola 18 chikuwonetsedwa mu (c).
Monga momwe zasonyezedwera mu Chithunzi 7c, kukulitsa nthawi ya MA mpaka maola 18 kunapangitsa kuti pakhale zolakwika zazikulu za lattice pamodzi ndi kusintha kwa pulasitiki. Pa gawo lapakati la njira ya MA, ufawo umakhala ndi zolakwika zosiyanasiyana, kuphatikizapo zolakwika zomangira, zolakwika za lattice, ndi zolakwika za nsonga (Chithunzi 7). Zolakwika izi zimapangitsa kuti timbewu tating'onoting'ono tigawikane m'malire a tirigu wawo kukhala tinthu tating'onoting'ono tosakwana 20 nm (Chithunzi 7c).
Kapangidwe kake ka ufa wa Cu50Z30Ni20 komwe kamaphikidwa kwa maola 36 a MA kali ndi kapangidwe ka nanograins za ultrafine zomwe zili mu amorphous fine matrix, monga momwe zasonyezedwera mu Chithunzi 8a. Kusanthula kwa EDS kwa m'deralo kunawonetsa kuti ma nanoclusters omwe awonetsedwa mu Chithunzi 8a anali ogwirizana ndi zinthu zosakonzedwa za Cu, Zr ndi Ni powder alloying. Nthawi yomweyo, kuchuluka kwa Cu mu matrix kunasinthasintha kuchokera ku ~32 at.% (dera lopanda mafuta) mpaka ~74 at.% (dera lolemera), zomwe zikusonyeza kupangika kwa zinthu zosiyanasiyana. Kuphatikiza apo, ma SADP ofanana a ufa omwe amapezeka pambuyo pophikidwa pagawoli akuwonetsa mphete zoyambira ndi zachiwiri za halo-diffusing za gawo lopanda mafuta, zomwe zimalumikizana ndi mfundo zakuthwa zogwirizana ndi zinthu zosaphika za alloying, monga momwe zasonyezedwera mu Chithunzi 8b.
Kupitirira 36 h-Cu50Zr30Ni20 ufa wa nanoscale mawonekedwe am'deralo.(a) Chithunzi chowala chamunda (BFI) ndi (b) SADP ya ufa wa Cu50Zr30Ni20 womwe wapezeka mutapera kwa maola 36 MA nthawi.
Pafupi ndi kumapeto kwa njira ya MA (maola 50), ufa wa Cu50(Zr50−xNix), X; 10, 20, 30 ndi 40 at.% nthawi zonse amakhala ndi mawonekedwe a labyrinthine amorphous phase monga momwe zasonyezedwera pa Chithunzi 9a–d. Mu SADP yofanana ya kapangidwe kalikonse, palibe ma diffraction ofanana ndi mfundo kapena ma pattern akuthwa a annular omwe sanapezeke. Izi zikusonyeza kuti palibe chitsulo chosakonzedwa chomwe chilipo, koma ufa wa alloy wosapangidwa umapangidwa. Ma SADP ogwirizana awa omwe akuwonetsa ma pattern a halo diffusion adagwiritsidwanso ntchito ngati umboni wa chitukuko cha magawo osasinthika muzinthu zomaliza za chinthucho.
Kapangidwe kake ka chinthu chomaliza cha dongosolo la MG Cu50 (Zr50−xNix). FE-HRTEM ndi mawonekedwe ofananira a nanobeam diffraction (NBDP) a (a) Cu50Zr40Ni10, (b) Cu50Zr30Ni20, (c) Cu50Zr20Ni30 ndi (d) Cu50Zr10Ni40 omwe apezeka patatha maola 50 a MA.
Kukhazikika kwa kutentha kwa kutentha kwa kusintha kwa galasi (Tg), gawo lamadzimadzi lozizira (ΔTx) ndi kutentha kwa crystallization (Tx) monga momwe zilili ndi Ni (x) ya dongosolo la Cu50(Zr50−xNix) lafufuzidwa pogwiritsa ntchito differential scanning Calorimetry (DSC) ya zinthu zomwe zili pansi pa kuyenda kwa mpweya wa He. Zotsatira za DSC za ufa wa aloyi wa Cu50Zr40Ni10, Cu50Zr30Ni20 ndi Cu50Zr10Ni40 womwe umapezeka pambuyo pa nthawi ya MA ya maola 50 zikuwonetsedwa mu Chithunzi 10a, b, e, motsatana. Pomwe DSC curve ya amorphous Cu50Zr20Ni30 ikuwonetsedwa padera mu Chithunzi 10c. Pakadali pano, chitsanzo cha Cu50Zr30Ni20 chomwe chimatenthedwa mpaka ~700 °C mu DSC chikuwonetsedwa mu Chithunzi 10d.
Kukhazikika kwa kutentha kwa ufa wa Cu50(Zr50−xNix) MG womwe wapezeka patatha nthawi ya MA ya maola 50, monga momwe zasonyezedwera ndi kutentha kwa kusintha kwa galasi (Tg), kutentha kwa crystallization (Tx), ndi dera lamadzimadzi lozizira (ΔTx). Ma thermograms osiyanasiyana a calorimeter (DSC) a (a) Cu50Zr40Ni10, (b) Cu50Zr30Ni20, (c) Cu50Zr20Ni30 ndi (e) Cu50Zr10Ni40 MG alloy powders patatha nthawi ya MA ya maola 50. Kapangidwe ka X-ray diffraction (XRD) ka chitsanzo cha Cu50Zr30Ni20 chomwe chatenthedwa mpaka ~700 °C mu DSC kakuwonetsedwa mu (d).
Monga momwe zasonyezedwera pa Chithunzi 10, ma curve a DSC a zinthu zonse zokhala ndi kuchuluka kosiyana kwa Ni (x) akuwonetsa milandu iwiri yosiyana, imodzi ya endothermic ndi inayo ya exothermic. Chochitika choyamba cha endothermic chikufanana ndi Tg, pomwe chachiwiri chikugwirizana ndi Tx. Dera lopingasa lomwe lilipo pakati pa Tg ndi Tx limatchedwa subcooled liquid region (ΔTx = Tx - Tg). Zotsatira zake zikuwonetsa kuti Tg ndi Tx ya chitsanzo cha Cu50Zr40Ni10 (Chithunzi 10a), chomwe chili pa 526°C ndi 612°C, chimasuntha zomwe zili (x) kukhala 20 at.% kupita kumbali yotsika ya kutentha ya 482°C ndi 563°C ndi kuchuluka kwa Ni (x), motsatana, monga momwe zasonyezedwera pa Chithunzi 10b. Chifukwa chake, ΔTx ya Cu50Zr40Ni10 imatsika kuchokera pa 86 °C (Chithunzi 10a) mpaka 81 °C ya Cu50Zr30Ni20 (Chithunzi 10a). 10b). Pa aloyi ya MG Cu50Zr40Ni10, zinaonedwanso kuti mtengo wa Tg, Tx ndi ΔTx unatsika kufika pa 447°C, 526°C ndi 79°C (Chithunzi 10b). Izi zikusonyeza kuti kuwonjezeka kwa kuchuluka kwa Ni kumabweretsa kuchepa kwa kutentha kwa aloyi ya MG. Mosiyana ndi zimenezi, mtengo wa Tg (507 °C) wa aloyi ya MG Cu50Zr20Ni30 ndi wotsika kuposa wa aloyi ya MG Cu50Zr40Ni10; komabe, Tx yake ikuwonetsa mtengo wofanana ndi woyamba (612 °C). Chifukwa chake, ΔTx ikuwonetsa mtengo wapamwamba (87°C), monga momwe zasonyezedwera pa Chithunzi 10c.
Dongosolo la MG Cu50(Zr50−xNix), pogwiritsa ntchito MG Cu50Zr20Ni30 alloy monga chitsanzo, limapangika kudzera mu exothermic peak yakuthwa kupita ku magawo a kristalo a fcc-ZrCu5, orthorhombic-Zr7Cu10 ndi orthorhombic-ZrNi (Chithunzi 10c). Kusintha kwa gawo losasinthika kukhala kristalo kunatsimikiziridwa ndi XRD ya chitsanzo cha MG (Chithunzi 10d), chomwe chinatenthedwa mpaka 700 °C mu DSC.
Chithunzi 11 chikuwonetsa zithunzi zomwe zinajambulidwa panthawi yopopera mankhwala ozizira yomwe ikuchitika pa ntchito yomwe ikuchitika panopa. Mu kafukufukuyu, tinthu ta ufa tofanana ndi galasi tomwe tinapangidwa pambuyo pa nthawi ya MA ya maola 50 (potenga Cu50Zr20Ni30 mwachitsanzo) tinagwiritsidwa ntchito ngati zinthu zopangira mabakiteriya, ndipo mbale yachitsulo chosapanga dzimbiri (SUS304) inaphimbidwa ndi ukadaulo wopopera mankhwala ozizira. Njira yopopera mankhwala ozizira inasankhidwa kuti iphimbidwe mu mndandanda wa ukadaulo wopopera mankhwala otentha chifukwa ndi njira yothandiza kwambiri mu mndandanda wa ukadaulo wopopera mankhwala otentha ndipo ingagwiritsidwe ntchito pazinthu zotenthetsera kutentha monga ufa wa amorphous ndi nanocrystalline, zomwe sizimasinthidwa ndi gawo. Ichi ndiye chinthu chachikulu pakusankha njira iyi. Njira yopopera mankhwala ozizira imachitika pogwiritsa ntchito tinthu tating'onoting'ono tomwe timasintha mphamvu ya kinetic ya tinthuto kukhala pulasitiki yosinthika, kupsinjika ndi kutentha ikagundana ndi substrate kapena tinthu tating'onoting'ono tomwe tinayikidwa kale.
Zithunzi za m'munda zikuwonetsa njira yozizira yopopera yomwe imagwiritsidwa ntchito pokonzekera kasanu motsatizana kwa MG coating/SUS 304 pa 550 °C.
Mphamvu ya kinetic ya tinthu tating'onoting'ono, komanso mphamvu ya tinthu tating'onoting'ono tomwe timapanga, ziyenera kusinthidwa kukhala mitundu ina ya mphamvu kudzera mu njira monga kusintha kwa pulasitiki (kuyanjana koyamba kwa tinthu tating'onoting'ono ndi tinthu tating'onoting'ono mu substrate ndi kuyanjana kwa tinthu), voids Kuphatikiza, kuzungulira kwa tinthu tating'onoting'ono, kupsinjika ndipo pamapeto pake kutentha 39. Kuphatikiza apo, ngati si mphamvu zonse za kinetic zomwe zikubwera zimasinthidwa kukhala mphamvu ya kutentha ndi kupsinjika, zotsatira zake zimakhala kugundana kosalala, zomwe zikutanthauza kuti tinthu tating'onoting'ono timangobwerera m'mbuyo pambuyo pa kugunda. Zawonetsedwa kuti 90% ya mphamvu ya kugwedezeka yomwe imagwiritsidwa ntchito ku tinthu tating'onoting'ono/substrate imasinthidwa kukhala kutentha kwapafupi 40. Kuphatikiza apo, pamene kupsinjika kwa kugwedezeka kukugwiritsidwa ntchito, kuchuluka kwa kupsinjika kwa pulasitiki kumakwaniritsidwa m'dera la tinthu tating'onoting'ono/substrate munthawi yochepa kwambiri 41,42.
Kusintha kwa pulasitiki nthawi zambiri kumaonedwa ngati njira yotaya mphamvu, kapena makamaka, gwero la kutentha m'dera la interfacial. Komabe, kuwonjezeka kwa kutentha m'dera la interfacial nthawi zambiri sikukwanira kupanga kusungunuka kwa interfacial kapena kulimbikitsa kwambiri kufalikira kwa atomiki. Palibe chofalitsa chomwe olembawo akudziwa chomwe chimafufuza momwe ufa wachitsulo wagalasi uwu umakhudzira kumatirira kwa ufa ndi kuunjikana komwe kumachitika pamene njira zoziziritsira zozizira zimagwiritsidwa ntchito.
BFI ya ufa wa aloyi wa MG Cu50Zr20Ni30 ikuwoneka mu Chithunzi 12a, chomwe chidapakidwa pa SUS 304 substrate (Zithunzi 11, 12b). Monga momwe chithunzichi chikusonyezera, ufa wopakidwa umasunga kapangidwe kawo koyambirira kopanda mawonekedwe chifukwa uli ndi kapangidwe kofewa kopanda mawonekedwe a kristalo kapena zolakwika za lattice. Kumbali ina, chithunzichi chikuwonetsa kukhalapo kwa gawo lakunja, monga momwe ma nanoparticles omwe amaphatikizidwa mu MG-coated powder matrix (Chithunzi 12a) amasonyezera. Chithunzi 12c chikuwonetsa mawonekedwe a nanobeam diffraction pattern (NBDP) ogwirizana ndi dera I (Chithunzi 12a). Monga momwe zasonyezedwera mu Chithunzi 12c, NBDP ikuwonetsa mawonekedwe ofooka a halo diffusion a kapangidwe ka amorphous ndipo imagwirizana ndi ma patches akuthwa ofanana ndi crystalline large cubic Zr2Ni metastable plus tetragonal CuO phase. Kupangidwa kwa CuO kungatchulidwe chifukwa cha okosijeni wa ufa poyenda kuchokera ku nozzle ya spray gun kupita ku SUS. 304 panja pansi pa madzi othamanga kwambiri. Kumbali ina, kupangidwa kwa ufa wagalasi wachitsulo kunapangitsa kuti pakhale magawo akuluakulu a cubic pambuyo popopera mankhwala ozizira pa 550 °C kwa mphindi 30.
(a) Chithunzi cha FE-HRTEM cha ufa wa MG wokutidwa pa (b) SUS 304 substrate (chithunzi cha chithunzi). Chizindikiro cha NBDP cha chizindikiro chozungulira chomwe chawonetsedwa mu (a) chawonetsedwa mu (c).
Pofuna kutsimikizira njira imeneyi yopangira tinthu tating'onoting'ono ta Zr2Ni tomwe timapanga cubic, kafukufuku wodziyimira pawokha adachitika. Mu kafukufukuyu, ufawo unathiridwa kuchokera ku mfuti yopopera pa 550 °C molunjika ku SUS 304 substrate; komabe, kuti afotokoze momwe ufawo umakhudzira, anachotsedwa mu SUS304 strip mwachangu momwe angathere (pafupifupi masekondi 60). Kuyesera kwina kunachitika momwe ufawo unachotsedwa mu substrate pafupifupi masekondi 180 mutayikidwa.
Zithunzi 13a,b zikuwonetsa zithunzi za mdima wakuda (DFI) zomwe zapezeka pofufuza ma microscopy a ma electron (STEM) a zinthu ziwiri zopopera zomwe zayikidwa pa SUS 304 substrates kwa masekondi 60 ndi masekondi 180, motsatana. Chithunzi cha ufa chomwe chayikidwa kwa masekondi 60 chilibe tsatanetsatane wa mawonekedwe, kusonyeza kusakhala ndi mawonekedwe (Chithunzi 13a). Izi zatsimikiziridwanso ndi XRD, yomwe idawonetsa kuti kapangidwe ka ufa uwu kanali kopanda mawonekedwe, monga momwe zasonyezedwera ndi maxima yayikulu komanso yachiwiri yotulutsa mpweya yomwe yawonetsedwa pa Chithunzi 14a. Izi zikuwonetsa kusakhalapo kwa metastable/mesophase precipitation, komwe ufawo umasunga kapangidwe kake koyambirira kopanda mawonekedwe. Mosiyana ndi zimenezi, ufa womwe unapopera pa kutentha komweko (550 °C), koma unasiyidwa pa substrate kwa masekondi 180, udawonetsa kutsika kwa tinthu tating'onoting'ono, monga momwe zasonyezedwera ndi mivi mu Chithunzi 13b.