Izici zokusebenza kwephaneli yephaneli ye-carbon fibre aluminium foam sandwich ye-copper-deposit uma kuqhathaniswa nephaneli yesemishi le-aluminium foam evamile

I-sandwich ye-aluminium foam(AFS) amaphaneli anenhlanganisela yezimpawu zesakhiwo nokusebenza okufana nokuminyana okuphansi, amandla athile aphezulu, ukumuncwa kwamandla avumayo, amandla okudambisa, kanye nokuvikela i-electromagnetic. Lezi zakhiwo ezinhle kakhulu zenza i-AFS ibe namandla amakhulu ku-aerospace, ezokuthutha, nezinkundla zasolwandle. Uma kuqhathaniswa namagwebu ensimbi amancane, amapuleti ensimbi angaphandle e-AFS angavala ngempumelelo igwebu futhi athuthukise izici zawo zemishini ezibanzi, njengokushuba namandla okugoba. Ngokuvamile, i-AFS yenziwa ngendlela yokunamathela enamathelayo, ehlanganisa ukunamathisela igwebu le-aluminium kumaphaneli ensimbi aqinile kusetshenziswa i-epoxy resin adhesive.

Nakuba indlela ye-adhesive bonding ithuthukisa ngempumelelo ukuncibilika kwesakhiwo, ihambisana nemikhawulo, okuhlanganisa nezinselele ekusetshenzisweni kabusha kanye nokuba sengozini yokwehluleka kwe-delamination ngaphansi kwezimo ezishisa kakhulu noma ezigqwalile. Ukuze kubhekwane nale mikhawulo, imizamo ebanzi yocwaningo inikezelwe ekuzuzeni ukuhlangana kwe-metallurgical phakathi kwephaneli nesendlalelo esiyinhloko.

Njengamanje, izindlela eziyinhloko zokulungiselela i-AFS okuhloswe ngazo ukuzuza ukuhlanganisa i-metallurgical ngokuvamile zihlukaniswa ngezigaba ezintathu: ukushisela, ukuncibilikisa amagwebu, kanye nendlela yokupakisha eyimpuphu yensimbi. Phakathi kwalezi zindlela, indlela yokupakisha eyimpuphu yensimbi ithathwa njengephakeme yokulawula ukwakheka kwezimbotshana kanye nokufeza amagwebu asezingeni eliphansi lokushisa. Umsebenzi wethu wangaphambilini wasebenzisa lobu buchwepheshe ukwenza i-AFS yosayizi omkhulu enezindawo zokunweba ezingcono kanye nesakhiwo samaselula sezinhlelo zokusebenza zezimboni.

Kodwa-ke, ngenxa yezakhiwo ezicindezelayo eziphansi ze-foam core, ukuthuthukiswa kwamandla emishini ye-AFS kunomkhawulo, ngakho-ke ukuthuthukiswa okuqhubekayo kwamandla we-foam core kubalulekile ku-AFS.

Kuze kube manje, izindlela ezivamile zibikwe ukuthuthukisa izakhiwo ezicindezelayo zemishini yei-aluminium foamzimi kanje: ukwelashwa kwendawo, ukwelashwa ukushisa, kanye nokuqiniswa ngokungeza izinhlayiya, imicu, izakhi ingxubevange, njll Phakathi kwazo, imicu ye-carbon emifushane ene-low density, i-high elastic modulus, ne-aspect ratio enkulu idonsele ukunakwa okubanzi njengezinto ezithembisayo zokuqinisa. Ngaphezu kwalokho, i-metalization engaphezulu ye-carbon fibers, nge-electroplating noma i-chemical plating efana ne-copper plating noma i-nickel plating, ithuthukisa nakakhulu ukumanzisa kwemicu ye-carbon ekuncibilikeni kwe-aluminium futhi igwema ukusabela okulimazayo kokuhlangana phakathi kwe-carbon fibers ne-aluminium encibilikayo. I-carbon fiber emfushane manje isetshenziswa kabanzi ukuqinisa izinhlanganisela ze-aluminium matrix.

Bhav Singhetal. kulungiswe imicu yekhabhoni eboshwe ngethusi eqiniswe izinhlanganisela ze-aluminium matrix ngendlela yokusakaza. Muetal. izinhlanganisela ze-aluminium matrix ezenziwe zaqiniswa ngamafiber ekhabhoni enziwe nge-nickel kusetshenziswa indlela yokuphosa enama-roll amabili. Imiphumela yabonisa ukuthuthuka okuphawulekayo kumandla aqinile wezinhlanganisela ngokungezwa kwe-carbon fibers. Nokho, kube nocwaningo olulinganiselwe olwenziwe kuloi-aluminium foam iqinisiwenge-copper-coated carbon fibers. I-Caoetal. amafayibha ekhabhoni ahlanganiswe ngethusi okokuqala aqinise igwebu le-aluminium ngokusebenzisa indlela yokuncibilika kwegwebu. Imiphumela ibonisa ukuthi i-0.35 vol% ye-Cf ingakwazi ukuzinzisa igwebu le-aluminium ngokuvimbela ukugqashuka kwefilimu ewuketshezi, futhi lapho inani lemicu engeziwe egwebu lizinza kakhulu. Muetal. wabonisa ukuthi izakhiwo ezimanzi ze-aluminium Foam ezilungiselelwe indlela yokuncibilika kwegwebu zathuthukiswa kakhulu ngokufakwa kwe-Cf.

Ngakho-ke, kungaphethwa ngokuthi ukwengezwa kwe-Cf kungaba isu elisebenzayo lokuthuthukisa ngasikhathi sinye ukuqina kwegwebu kanye nezakhiwo zemishini.amagwebu e-aluminium. Ngaphezu kwalokho, akuzange kube nemibiko mayelana namaphaneli e-carbon fibers afakwe ngethusi aqiniswe ngamaphaneli amasemishi e-aluminium foam alungiswe ngendlela ye-powder metallurgy, ekhuthaza abacwaningi ukuba benze izifundo ezijulile kulo mkhakha.

Kuye kwenziwa izifundo eziningi ngendlela ye-nucleation nokuzinza kweamagwebu e-aluminiumngokwengezwa kwezigaba zokuqinisa. Umehluko wenombolo yembobo kanye ne-pore morphology,

njengosayizi, ukusatshalaliswa, kanye nokuma, ngokuvamile kubangelwa izindlela ze-nucleation nokuzinza. Imiphumela ye-nucleation ehlukahlukene kanye nezindlela zokuzinzisa inethiwekhi ye-oxide ohlelweni lwe-powder metallurgy kuye kwaphenywa ngokuphelele. Izimpushana ze-Quaternary alloy ezihlanganisa i-Al–Si–Mg–Cu ezisetshenziswe kuleli phepha ziye zabonisa amazinga okukhula angavamile namazinga okushisa anamagwebu aphansi, nezinga lokushisa eliqinile elingu-507 ◦C kanye nezinga lokushisa elingu-liquidius elingu-596 ◦C. Noma kunjalo, kukhona ukuntuleka kocwaningo mayelana nendlela yokwenza i-nucleation, ukuzinza, kanye nezakhiwo ezicindezelayo zemishini ye-powder compacts equkethe lokhu kwakheka kwe-alloy, ikakhulukazi uma kuhlanganiswa i-Cf. Emisebenzini yangaphambilini, uphenyo lwezinqubo ze-nucleation kanye nokuzinzisa kwenziwa ngokuyinhloko ngokusebenzisa izindlela ezingezona endaweni, ezibandakanya ukuhlaziywa kwe-tomographic yamasampuli apholile ngokushesha ngemva kokuphazanyiswa kwegwebu. Ngeshwa, i-nucleation yebhamuza le-submicron ngokuyinhloko yenzeka phakathi nokushisisa kwesandulela futhi inweba ngokushesha phakathi kwezikhawu zesikhathi ezisukela ku-100 ms ukuya ku-1 s, ngokuvamile iveza izinselele zokubhekwa kwesikhathi sangempela. Inqubo yesimanje ye-synchrotron emisebeni yeX-ray imaging inamandla aphezulu kanye nesixazululo se-spatiotemporal, okuvumela ukubonwa kwesikhathi sangempela, endaweni ye-nucleation kanye nenqubo yokukhula kwamagwebu e-aluminium emazingeni okushisa aphakeme. Njengamanje, abacwaningi abalinganiselwe kuphela abaye bahlola i-kinetics enegwebu ye-Al-Si-Mg alloy powder ngemisebe ye-synchrotron. Isibonelo, i-García-Morenoetal. kubike izenzakalo ezibalulekile eziguquguqukayo kugwebu lwe-aluminium ewuketshezi, okuhlanganisa i-nucleation nokukhula, ukuhlelwa kabusha kwebhamuza, ukuhoxiswa koketshezi, ukuhlanganisana, nokugqabuka kwefilimu. Kamm et al. wafunda inqubo ye-nucleation kanye nokukhula kwe-AlSi8Mg4 aluminium foam ngemisebe ye-synchrotron. Ukuthola kwabo kubonise ukuthi i-hydrogen ekhiqizwa ngokubola kwama-adsorbates endaweni yempushana yensimbi imelela enye indlela ebalulekile yokwenziwa kwe-nucleation. Nokho, ukusebenzisana phakathi kwezingxenye ezandulelayo kuyinkimbinkimbi, futhi amandla okukhiya amagwebu angathonywa ukwakheka kwawo. Kuzo zombili i-Al-Si-Cu-Mg powder system kanye ne-Al-Si-Cu-Mg powder system ene-Cf eyengeziwe, ukuqonda nokuhlola ukuqaliswa nokukhula kwegwebu lensimbi kubalulekile ekuthuthukisweni kwesakhiwo segwebu ukuthuthukisa izakhiwo. ngezicelo.

Kulo msebenzi, i-CF/AFS kanye ne-AFS ene-metallurgical interfacial bonding yalungiselelwa indlela yokupakisha ye-powder metallurgy. Ukuvela kwamabhamuza kwe-Cf/AFS kanye ne-AFS kwabonwa ku-situ ngemisebe ye-synchrotron ukuze kwembule indlela ye-Cf ku-bubble nucleation, ukukhula nokuhlanganiswa, nokuzinza. Ukwengeza, i-Cf/AFS kanye ne-AFS kufakwe amagwebu ku-620 ◦C imizuzu engu-15 esithandweni somlilo segumbi. Kamuva, ukusatshalaliswa kosayizi wembotshana, i-pore microstructure, kanye nezakhiwo ezicindezelayo zemishini yamasampula anegwebu kwaphawulwa futhi kwahlolwa. Ngokusekelwe ezifundweni ezishiwo ngenhla, ukwakheka namandla okucindezela kwe-Cf/AFS kanye ne-AFS kwahlolwa ngokuhlelekile.

2. Izinto kanye nezindlela

2.1. Ama-Raw material

Kwasetshenziswa izinto zokusetshenziswa eziyisithupha ekulungiseni i-AFS kanye ne-Cf/AFS: I-Al powder (usayizi ojwayelekile: 45 μm, ubumsulwa > 99.70%), i-Si powder (usayizi ojwayelekile: 38 μm, ubumsulwa > 99.50%), i-Cu powder (usayizi ojwayelekile: 38 μm, ubumsulwa > 99.90%), Mg powder (usayizi omaphakathi: 75 μm, ubumsulwa >99.70%), i-TiH2 powder (usayizi ojwayelekile: 45 μm, ukuhlanzeka >99.70%), kanye ne-carbon fiber eboshwe ngethusi (usayizi omaphakathi: 1～2 mm, ukujiya kwe-copper-coated: 1.4 μm).

2.2. Ukwenziwa kwe-CF/AFS

I-schematic yendlela yokupakisha ye-powder metallurgy yokupakisha iboniswa kuUmdwebo 1. Phakathi nesigaba sokuxuba, i-quaternary alloy AlSi6Mg4Cu4 powder yalungiswa, nezimpushana ze-Al, Si, Cu, ne-Mg ngezilinganiso ze-86 wt%, 6 wt%, 4 wt%, kanye ne-4 wt%, ngokulandelana. I-1 wt% i-TiH2 powder ene-oxidized (ukwelashwa kokushisa emoyeni kwe-1.5 h ku-470 ◦C) yengezwe njenge-ejenti evuthelayo ekhulula i-H2 ngokushesha ekushiseni okuncibilika kwandisa ukuncibilika. Ukwengeza, i-0.5 wt% ye-carbon fibers ifakwe njengezigaba zokuqinisa. Ngokuphawulekayo, ukuze kuthuthukiswe ukumanzisa nokuvimbela ukusabela okuyingozi njenge-Al4C3 kusixhumi esibonakalayo esincibilikisa i-fiber-aluminium ngesikhathi sokukhihliza amagwebu, imicu yekhabhoni yayimbozwe ngethusi nge-electroplating. Inqubo ye-electroplating ichazwe ku-Refs.Umdwebo 2ikhombisa imicu ye-carbon eboshwe ngethusi etholwe yinqubo yokucwenga engenawo amandla. I-coating inokuhlanganiswa okufanayo nokuqhubekayo kwendawo ye-fiber(Umdwebo 2(a)–(b)). Kamuva, ukwakheka okuhlukene kwengxubevange okusetshenziswe kulolu cwaningo kulungiswe ngokuxutshwa kahle izimpushana ezishiwo ngenhla ne-Cf nangaphandle kwayo kumxube wezinhlangothi ezintathu amahora angu-3. I-powder exutshwe ngokulinganayo ifakwe ngaphakathi kwendawo evaliwe, ilandelwa izinqubo zokugoqa ezibandayo nezishisayo.

Isiteji sokugoqa esibandayo siwukhipha ngempumelelo umoya ngaphakathi kwemigodi kanye nezikhala eziphakathi kwezinhlayiya ngochungechunge lwamaphasi amaningi kanye nokucindezelwa okuncane. Isiteji sokuginqika esishisayo siqinisekisa ukuthi isandulela sifinyelela ukuminyana okuhlobene okudlula ama-98% ngokusebenzisa ukuguquguquka okuhlangene kwephaneli kanye nempushana, okusiza inqubo yokukhipha amagwebu elandelayo. Amapharamitha enqubo yokugoqa anemininingwane achazwe kumaRef. I-AFS kanye ne-Cf/AFS izandulela ezifomayo zitholakala ngenqubo eshiwo ngenhla. Ekugcineni, zombili izandulela ezigwedlayo zashiswa ku-620 ◦C imizuzu engu-15 ukuze kwenziwe izibonelo ze-Cf/AFS kanye ne-AFS, ezasetshenziselwa ukuhlaziya usayizi wezimbotshana, ukuhlukaniswa kwezinhlamvu ezincane, kanye nokuhlolwa kwezakhiwo ezicindezelayo.

2.3. Uhlamvu kanye nezindlela zokuhlola

2.3.1. Ukulingiswa kwe-Microstructural

I-Microstructure morphology ye-Cf/AFS kanye ne-AFS yaphenywa yi-field emission scanning electron microscopy (SEM, Zeiss Ultra Plus). I-Energy dispersive spectroscopy (EDS) yasetshenziswa ukukhomba ukwakheka kwezigaba ezahlukahlukene ezindongeni zamaseli amasampula anegwebu. Izingxenye ze-longitudinal zamasampuli zitholwe ngokusika ama-specimens anegwebu kusetshenziswa umshini wokukhipha i-electro-discharging (EDM, DK7745). Ngemva kwalokhu, izingxenye ze-longitudinal zesampula zapendiwa ngopende zase zigaywa futhi zapholishwa kusetshenziswa i-sandpaper engu-800-grit ne-1500-grit, ngokulandelana. Ekugcineni, amadayamitha amaseli alinganayo (i-Dmean) esiqephu esiphambanisayo sesifanekiso esiphucuziwe anqunywa kusetshenziswa isofthiwe yokuhlaziya izithombe, i-Image Pro Plus 6.0.

Umdwebo 1.I-Schematic yendlela yokupakisha eyimpuphu yensimbi.

Umdwebo 2.Izithombe ze-SEM (a) ze-carbon fibers ezimbozwe ngethusi, futhi (b) zibonisa ukubuka okukhulisiwe kwesifunda esimakwe yisikwele esibomvu kokuthi (a). Izithombe (c) kanye no-(d) ziyimiphumela ye-EDS yephuzu A ku-(b).

Umdwebo 3.Umdwebo wohlelo lokusethwa kokuhlolwa kwemisebe ye-synchrotron.

2.3.2. Ukubonwa kogwebu ku-in-situ ngemisebe ye-synchrotron

Umdwebo wohlelo lokusethwa kokuhlolwa kwemisebe ye-synchrotron udwetshiweUmdwebo 3. Ukuhlola kwenziwe ku-beamline 4W1A ye-Beijing Synchrotron Radiation Facility (BSRF, Beijing Institute of High Energy Physics, Chinese Academy of Sciences, China). Ngokungafani ne-imaging evamile yokumuncwa-nokugqama, leli phepha lisebenzisa isithombe sokugqama kwesigaba ngomthombo wokukhanya we-Synchrotron Radiation. Le ndlela ibhekana nemikhawulo yokuthwebula kwendabuko kokumuncwa, okungasebenzi ekuboneni ngeso lengqondo izinto ezimunca buthaka. Inqubo yokukhihliza amagwebu yesampula yenziwa ngaphakathi kwesithando somlilo esigwebuzelayo esiklanywe ngokwezifiso, esinefasitela lesikwele esingu-15 mm by 15 mm elibekwe ngendlela eqonde ngqo lapho kuqondiswa khona i-X-ray. Usayizi wesampula, njengoba kuboniswe ku-Fig. 3, ukala u-15 mm × 15 mm × 2 mm. Isampula ifakwe esikhunjini esinamagwebu esihlanganisa inombolo ethile yamashidi e-ceramic. Kuyo yonke inqubo yokukhihliza amagwebu, ama-X-reyi angadlula kusampula futhi athathwe ikhamera ye-charge-coupled device (CCD). Umthombo we-X-ray okhethiwe wawusebenza ngamandla angu-20 Kev, futhi kwasetshenziswa usayizi omkhulu wokubuka ongu-7.4 mm × 7.4 mm ukuze kunikwe amandla ukubhekwa okuphelele kwayo yonke inqubo yokukhihliza amagwebu.

Kuyaphawuleka ukuthi amasampula abhekiwe abekwe ngendlela eqondile kukho kokubili isiqondiso sokugingqika kanye nesiqondiso se-tangential. Kokubili izandulela eziqukethe i-0.5 wt% Cf kanye nalabo abangenayo i-0.5 wt% Cf babe namaphaneli abo aseceleni asusiwe ezinhlangothini zombili zamasampuli kusetshenziswa i-EDM. Umthelela we-Cf ezicini ezinogwebu zegwebu le-aluminium waphenywa. Ngaphezu kwalokho, izandulela ezinokwakheka okuhlukene zazifakwe amagwebu esithandweni sokushisa esifanayo ezingeni lokushisa elihleliwe elingu-620 ◦C.

2.3.3. Ukuhlolwa kwezakhiwo zemishini yokucindezela

Izibonelo zokucindezela zanqunywa zibe izibonelo ze-cylindrical ezinobude obungu-23 mm nobubanzi obungu-20 mm nge-EDM, futhi zonke iziqondiso zaqinisekiswa ukuthi zihlanganisa okungenani ama-pores angu-10 aphelele ukuze kugwenywe umphumela wesayizi. Ukuhlolwa kokuminyanisa kwe-Quasi-static kwenziwa ngokulandela amazinga e-ISO13314–2011 kanye ne-GB/T31930–2015, kusetshenziswa umshini wokuhlola we-electron universal material we-AG-XPLUS onomthamo omkhulu wokulayisha ongu-100 KN. Amasampula amathathu ahlolwe eqenjini ngalinye, futhi amajika okucindezela okucindezelayo kuleli phepha amelela imiphumela emaphakathi etholwe kumasampula amathathu ahloliwe. Zonke izivivinyo zenziwa ngaphansi kokulawulwa kokufuduka, kugcinwe isivinini esingaguquki se-cross-head esingu-2 mm/min (okuhambisana nesilinganiso sokuqala sokucindezeleka esingu-10− 3 s− 1) ekamelweni lokushisa.

Umdwebo 4.Izithombe zemisebe ye-synchrotron evelelwe yisikhathi yenqubo ye-Cf/AFS yokwenza amagwebu: (a) isandulela esingenagwebu kumzuzu we-t0 we-380 ◦C; (b)–(c) ukuhlakazwa kwe-elemental copper kanye nohlobo lwe-nucleation yohlobo lwe-II ngesikhathi sokuncibilika kwesandulela; (d)–(g) i-nucleation ehlukahlukene kanye nezinqubo zokukhula zamabhamuza; kanye (h)–(i) namabhamuza ahlanganayo futhi agqabuke.

3. Imiphumela kanye nengxoxo

3.1. Ukuziphatha kokugwebu ku-situ ngaphansi kwemisebe ye-synchrotron

3.1.1. Ukuvela kwegwebu kwe-CF/AFS

Umdwebo 4ibonisa uchungechunge lwezithombe zemisebe ye-synchrotron ebonisa inqubo yokukhihliza amagwebu ye-Cf/AFS. Izithombe zangempela ze-CF/AFS(Umdwebo 4 (a))athwetshulwa lapho i-matrix isesimweni esiqinile kokuthi 380 ◦C, futhi lesi sikhathi samiswa njengo-t0. Uma kuqhathaniswa nezinye izingxenye zesandulela, i-Cf ibonakala imnyama ngaphakathi kwe-matrix ecebile kakhulu ye-aluminium empunga. Lokhu kungabangelwa okuqukethwe kwethusi okuphezulu endaweni yefayibha, njengoba kuboniswe kuUmdwebo 2(c)–(d), enesisindo esikhulu se-athomu esihlobene uma kuqhathaniswa nezinye izingxenye zesandulela. Ngaphezu kwalokho, iningi le-Cf libonwa lihlakazekile futhi lihlukene, kunokuba liqoqwe ndawonye, ​​njengoba kukhonjisiweUmdwebo 4(a). Lokhu kusho ukuthi ngokwengezwa okungu-0.5 wt% kwe-Cf, inqubo yokushukumisa amahora angu-3 ingafinyelela ngempumelelo isimo esifiswayo sokuhlakazeka.

Ku-t0+194s (njengoba kubonwe kuUmdwebo 4(b)), inani elikhulu lamabhamuza amhlophe, acishe abe yindilinga anobubanzi obusuka ku-90 μm kuya ku-180 μm angabonwa ku-matrix ye-aluminium empunga (imakwe ngomcibisholo obomvu). Inani lamabhamuza liqhubekile nokukhula phakathi kwamasekhondi angama-46, njengoba kuboniswe kuUmdwebo 4(c). Ukwengeza, olunye ushintsho oluphawulekayo olwenzeka ku-matrix ukuthi amanye amabhamuza amancane avamise ukwakheka ebusweni buka-Cf ngokuqalwa kokuhlakazeka kwe-Cu (okumakwe ngebhokisi elinamachashazi abomvu). Lesi simo cishe sihlotshaniswa nohlobo lwe-nucleation ye-II eyenzeka ngaphakathi kwe-copper equkethe i-powder compact. Kuyavunywa kabanzi ukuthi ukungezwa kwe-Cu kunciphisa kakhulu izinga lokushisa elincibilikayo lama-alloys. Lokhu kubangela ukuncibilika kwendawo eduze kwezinhlayiya zempushana ku-powder precursor equkethe impushana yethusi phakathi nenqubo yokushisisa, okukhiqiza inani elikhulu le-Al-Si-Mg-Cu quaternary eutectic eutectic encibilikayo emazingeni okushisa aphansi. I-quaternary eutectic melt pool ijwayele ukuba yisifunda esibuthakathaka ku-alloy futhi ijwayele ukuvela ku-nucleation. Ngenxa yalokho, amabhamuza maningi amathuba okuthi abe yinucleate futhi akhule eduze nendawo eboshwe ngethusi endaweni yefiber. Ngaphezu kwalokho, ingxenye yoketshezi ephansi ku-matrix ngalesi sikhathi ibangela amagesi asuka ekuboleni kwe-TiH2 ukuthi anqwabelene kalula ku-aluminum matrix. I-nucleation yohlobo lwe-II ingagwema ngempumelelo igesi enqwabelene ephoqelela i-matrix yengxenye yoketshezi ephansi futhi isakaze imifantu oketshezini, okuholela ekulahlekelweni okukhulu kwenani le-hydrogen.

Umdwebo 4(d)ikhombisa amabhamuza ekuqaleni e-nucleate futhi akhule endaweni ye-Cf njengoba i-matrix incibilika ngokuphelele, futhi izindawo zebhamuza zihambisana nongqimba olunamekwe ngethusi olunyamalalayo (emakwe ngebhokisi elinamachashazi abomvu). Kusungulwe kahle ukuthi ukungezwa kwezigaba zesibili kwandisa inani lezindawo ze-nucleation ezihlukahlukene, ngaleyo ndlela kunciphisa umgoqo wamandla wokwakhiwa kwamabhamuza amasha ngaphakathi kwe-alloy melt. Phakathi naleso sikhathi, izinga le-nucleation lihlobene nenani eliphelele le-nucleation elingafani nevolumu yeyunithi ngayinye. Ngakho-ke, kungaqashelwa ukuthi amabhamuza aqala ukuzungeza ezindaweni lapho imicu yekhabhoni ikhona futhi ande ngobude be-carbon fiber. Ngokukhula okwengeziwe kwengxenye yokuncibilika, amabhamuza amaningi amasha ayaqhubeka nokuvela kuwoUmdwebo 4(e)–4(g). Kodwa-ke, izinga lokuhlanganiswa kwendawo kanye nokuphuka kwamabhamuza lihamba kancane, okubonisa ukuthi amabhamuza anokuqina okuphezulu. Ku-t0+426s, inani lamabhamuza likhuphuka kakhulu, futhi

ivolumu eyandulelayo ibonisa ukwanda okukhulu(Umdwebo 4(h)). Ngaphezu kwalokho, ukwenzeka kokuhlangana kwebhamuza (okumakwe ngomcibisholo obomvu), lapho amabhamuza amancane amuncwa amakhulu ngenxa yokuvuthwa kuka-Ostwald, kuyinqubo engenakugwenywa ngesikhathi sokuvela kwamagwebu ensimbi [40]. Lesi simo sokuvuthwa siphinde sibangele ukubonakala kwenani elincane lamabhamuza amakhulu nangavamile (amakwe ngomcibisholo obomvu ku-Umdwebo 4(i)).

Umdwebo 5.Izithombe eziguquliwe isikhathi zenqubo yokugwaza kwe-AFS ezigabeni ezihlukene: (a) isandulela esingancibilikisiwe kumzuzu we-380 ◦C; (b) ukuhlakazwa kwe-elemental copper kanye nohlobo lwe-II nucleation ngesikhathi sokuncibilika kwesandulela; (c) izinqubo ze-nucleation kanye nokukhula kwamabhamuza; kanye (d)–(f) namabhamuza ahlanganayo futhi agqabuke.

3.1.2. Ukuvela kwe-Foam kwe-AFS

Umfanekiso wesi-5 ubonisa uchungechunge lwezithombe zemisebe ye-synchrotron ezibonisa inqubo yokugwedla ye-AFS. Ngokufanayo ne-Cf/AFS, isithombe sokuqala sokulandelana kwemisebe ye-synchrotron sathathwa lapho i-AFS isesigabeni esiqinile ku-380 ◦C (bonaUmdwebo 5(a)). Lapho i-matrix ishisiswe ngaphezu kwezinga lokushisa le-solidus, amabhamuza amancane amhlophe abonakala phakathiUmdwebo 5(b) no (c), okubangelwa ukubola kwe-TiH2 kanye nokuvela kwe-nucleation yohlobo lwe-II esifundeni sase-Cu-rich. Nokho, inani lamabhamuza akhiqizwayo kanye nokuminyana kwawo kokusabalalisa kuwoUmdwebo 5(c)iphansi ngokuphawulekayo uma iqhathaniswa neUmdwebo 4(c). Lokhu kuphakamisa ukuthi i-Cf/AFS ihlinzeka ngamashaneli amaningi okukhishwa kwegesi kwasekuqaleni ngesikhathi se-nucleation, ukuvimbela ukwakheka ngokweqile kwemifantu ku-aluminium matrix enengxenye encane yoketshezi.

Inombolo embalwa yezindawo ze-AFS nucleation kanye namathuba aphezulu okukhula kwebhamuza okungavamile uma kuqhathaniswa ne-Cf/AFS kungabonwa kusukelaUmdwebo 5(d)–(f). Ukuvela kwamabhamuza e-AFS akuvamile, futhi osayizi bawo babonisa ukushintshashintsha okubanzi ngenxa yokuhlalisana kwawo womabili amabhamuza anosayizi we-micrometer kanye namabhamuza amakhulu anosayizi wemilimitha ngokungajwayelekile (amakwe ngomcibisholo obomvu). Ngaphezu kwalokho, lokhu kungazinzi kanye nokungafani phakathi kwenqubo yokuqala ye-nucleation kungabangela ukungafani okukhulu kwesakhiwo sokugcina se-pore kanye nezakhiwo zemishini phakathi kwe-AFS ne-Cf/AFS.

3.2. Ukuhlaziywa kwe-Macrostructure

Ukuze uphenye umehluko we-macroscopic pore morphology kanye nobubanzi bembotshana phakathi kwe-AFS ne-Cf/AFS, izakhiwo zamasemishi ezimbili zalungiswa ngaphansi kwezimo zaselabhorethri ekushiseni okunegwebu okungu-620 ◦C imizuzu engu-15. Ama-macrostructures kanye nokusatshalaliswa kosayizi weseli we-AFS kanye ne-Cf/AFS kukhonjisiwe kuUmdwebo 6. Ukuqhathaniswa kwezingxenye eziqondile zamasampula ezinhlaka zamasemishi amabili kuveza ukuthi amagwebu e-Cf/AFS anamaseli acolekile kanye neziphambeko ezincane njengokuqhekeka noma ukuhlanganiswa kwamaseli (bonaUmfanekiso wesi-6 (b)). Ngokuphambene, njengoba kuboniswe kuUmdwebo 6(a), i-AFS ikhombisa ubuncane bembotshana obumpofu ngokuba khona kwezinye izimbotshana ezinkulu ngokungavamile. Phakathi naleso sikhathi, imbobo elingana nobubanzi be-AFS ne-Cf/AFS yayiyi-2.9 ± 0.2 mm kanye ne-1.9 ± 0.1 mm, ngokulandelana, okuphakamisa ukuthi ububanzi bembobo buphinde bucwengisiswe ngokungezwa kwe-Cf (bonaUmdwebo 6(c) no (d)).

Ukuvela kwesakhiwo se-pore kuthonywa izindlela ezimbili zokuncintisana: ukubola kwe-TiH2 kanye nokuhlanganiswa nokuphuka kwegwebu. Ukubola kwe-TiH2 kunomthelela ekwandeni kwenani le-nucleation, i-porosity, kanye nezinga lokunwetshwa, kuyilapho ukuhlangana nokuqhekeka kwamabhamuza kunciphisa inani lama-pores futhi kwandisa ububanzi bezimbotshana. Ukunciphisa ukuhlangana kwebhamuza kanye nemicimbi yokuqhekeka kunomthelela ekutholeni isakhiwo seselula esingcono. Ngakho-ke, ukuzinza okuphezulu kwegwebu kuyadingeka ukuze kugcinwe i-homogeneity yesakhiwo se-pore ngesikhathi senqubo yokukhipha amagwebu. Ku-Cf/AFS, ukungezwa kwe-Cf kuthuthukisa kakhulu ukumanzisa kwemicu ngokuncibilika kwe-aluminium. Ngokufana negwebu le-aluminium eliqinisiwe elibikiwe le-Cf [44] elilungiselelwe indlela yokuncibilika kwegwebu, ukungezwa kwe-Cf kusimamisa igwebu le-aluminium ngokuvimbela ukuqhekeka kodonga lweseli nokunciphisa ukuhlangana. Phakathi naleso sikhathi, i-Cf ingakha isakhiwo esifana nenetha odongeni lweseli, ekhiqiza amandla okuhlukanisa futhi ivimbele ukugqashuka kwamabhamuza, ngaleyo ndlela, ithuthukise ukwakheka kweseli, ukuzinza kwegwebu, kanye nokufana kokusatshalaliswa kwembobo.

3.3. Ukulingiswa kwe-Microstructural

Umdwebo 7(a)ikhombisa i-microstructure yodonga lwamaseli ngemva kokugwaza nge-AFS. Njengoba kubikwe nge-AlSi6Cu4Mg4 alloy foams, i-eutectic Al–Si, Mg2Si, Al2Cu, kanye ne-Al5Cu2Mg8Si6, akhona kungxubevange, evumelana nokutholwe ekuhlaziyweni kwe-EDSUmdwebo 7(b). Lezi zigaba eziphukayo zehlisa izakhiwo zemishini zegwebu le-aluminium ngokwenza buthaka udonga lwezimbotshana noma ngokusebenza njengomthombo wokuqhekeka ngesikhathi sokuguquguquka. Ngakho-ke, ukuthuthukisa izakhiwo zemishini yodonga lwama-pore ngokungezwa kwezigaba zokuqinisa kuyisu elisebenzayo nelisebenzayo.

Ku-Cf/AFS, ingabonwa kusukaUmdwebo 7(c) kanye (d)ukuthi i-Cf isatshalaliswa ngaphakathi kodonga lweseli noma emaphethelweni odonga lweseli, okubonisa ukuthi i-Cf inokumanzisa okuhle kakhulu ngokuncibilika kwe-aluminium. Ngaphezu kwalokho, kuyaphawuleka (bheka kuUmdwebo 7(d)) ukuthi inani elincane lesigaba esinciphile i-Al2Cu lakheka kusixhumi esibonakalayo phakathi kwamafayibha ne-aluminium encibilikayo. Lesi simo sinomthelela ekufinyeleleni isibopho esiqinile phakathi kwamafayili kanye ne-matrix. Ukuqhubeka kwalokhu kusabela kokusabalalisa kungabonwa ngendlela enembileUmfanekiso 4(a)–(c). Qaphela ukuthi, isigaba esinezimvula asiwahaqi ngokuphelele ama-carbon fibers, futhi isimo nenani lalokhu kusatshalaliswa kunenzuzo ku-Cf/AFS. Ngokusekelwe ocwaningweni luka-Lv et al, ezintweni eziyinhlanganisela ye-aluminium ye-aluminum eqinisiwe, kwaboniswa ukuthi inani elifanele lesigaba esinciphile lingathonya futhi lilawule amandla ebhondi ehlangana ubuso.

Umdwebo 6.Izigaba ezime mpo zesampula elimele (a) i-AFS kanye (b) ne-Cf/AFS. Ububanzi obulinganayo uma kuqhathaniswa neziqephu zengxenyana zendawo ezihambisana no-(a) no-(b) zivezwe kokuthi (c) kanye no-(d), ngokulandelanayo. Umugqa oqhubekayo oqinile ku-(c) kanye no-(d) umelela ukungena kwelogi evamile. Ukwehla (R2) kumelela ubuhle bokulingana.

Umdwebo 7.Izithombe ze-SEM (a) kanye (b) zibonisa ama-microstructures ahambisana nawoUmdwebo 6(a) AFS kanyeUmdwebo 6(b) Cf/AFS, ngokulandelana, ngaphezu kwalokho,Umdwebo 7(b) kanye (d) nokukhombisa ukukhuliswa kwasendaweni kweUmdwebo 7(a) kanye (c), ngokulandelana.

3.4. Indlela ye-CF yokuzinzisa igwebu le-Al–Si–Mg–Cu

Ngokusekelwe ekuhlaziyweni okukhulunywe ngenhla, ukumelwa okuhleliwe kwendlela yokukhipha amagwebu ku-Cf/AFS kanye ne-AFS kufinyezwa ku-Umdwebo 8. Umehluko obalulekile phakathi kwe-Cf/AFS ne-AFS esigabeni se-nucleation, ukukhula kwebhamuza, nesigaba sokuhlanganisa, kanye nesigaba sokuqina kancane kancane, njengoba kubonisiweUmdwebo 8(a) no (b).

Umdwebo 8.Umdwebo wohlelo lwe-Cf/AFS kanye ne-AFS yokuziphatha okugwebulile: (a) Cf/AFS; kanye (b) ne-AFS.

Esigabeni se-nucleation samagwebu e-AlSi6Cu4Mg4 alloy, amabhamuza ajwayele ukugcwala ngaphakathi kwe-liquid quaternary eutectic ezungeze izinhlayiya zethusi, kunokuba abe i-nucleate endaweni yezinhlayiya ze-TiH2. Lolu hlobo lwe-nucleation esifundeni esibuthakathaka se-precursor (uhlobo lwe-nucleation ye-II) lunikeza iziteshi zokuphunyuka ezengeziwe zamagesi akhishwe ukubola kwe-TiH2, ukugwema ukuqoqwa kwamagesi futhi kubangele ukuqhekeka ukuba kusakazeke ekuncibilikeni kwe-aluminium. Ukwengezwa kwamafayibha ekhabhoni ambozwe ngethusi ngokusobala kudala iziteshi eziningi zokukhulula i-H2. Nokho, njengoba ukuncibilika kwe-aluminiyamu kungenayo ingxenye yoketshezi eyanele kulesi sigaba, kunzima ngamabhamuza amancane kangako ukuba abe nomthombo owanele we-H2 ukuze aqhubeke nokukhula. Ngenxa yalokho, lawa mabhamuza amancane aqhuma ngaphakathi kokuncibilika njengoba izinga lokushisa likhuphuka. Uma i-precursor incibilika ngokuphelele, i-H2 ekhishwe ekuphenduleni kwe-dehydrogenation enobudlova ye-TiH2 izoba nucleate futhi ikhule ngokushesha ngokusekelwe iphuzu le-nucleation. I-Cf ihlinzeka ngezindawo eziningi ze-nucleation ezihlukahlukene zokukhiqiza amabhamuza, okwandisa kakhulu amazinga e-nucleation. Ngesikhathi esifanayo, ukuba khona kwe-Cf kuvimbela ngempumelelo ukuthintana nokuhlanganiswa kwamabhamuza ayinhloko futhi kugwema ukwakheka kwamabhamuza amakhulu ngokungavamile.

Ngesikhathi sokukhula nokuhlanganiswa kwamabhamuza, ukungezwa kwe-Cf kuthuthukisa kakhulu ukuzinza kwegwebu. Isizathu siwukuthi i-Cf ne-aluminium iyancibilika inokumanzisa okuhle, futhi imicu ingavaleleka kalula phakathi kwezindawo ezimbili zokuhlangana eziwuketshezi lwegesi ukuze zakhe isakhiwo senethiwekhi (njengoba kuboniswe ku-Umdwebo 7(c)). Njengoba ifilimu ewuketshezi incishiswa, imicu ingakwazi ukukhiqiza ingcindezi yokuhlukanisa ukuze imelane nokumunca emngceleni wethafa, ngaleyo ndlela ivimbele ifilimu ewuketshezi ukuthi ingaqhumi. Ngakho-ke i-Cf/AFS idinga isikhathi eside sokukhihliza amagwebu uma iqhathaniswa ne-AFS, ngokuzinza okuphezulu okungagcina ukufana kwesakhiwo sembobo ngesikhathi sokuvela kwegwebu.

Phakathi nesigaba sokuqina kancane, amabhamuza ku-Cf/AFS awasakhuli futhi imicu ishumekwe ngaphakathi kodonga lweseli (imakwe ngebhokisi elinamachashazi abomvu). Lokhu kugcinwa kwamafayibha kuvimbela ukumuncwa kwamabhamuza amancane ngamakhudlwana, njengoba kubonakala ekuvuthweni kwe-Ostwald, futhi kuvimbela ukuqhekeka kodonga lweseli ngenxa yokunwetshwa kokuqina. Ngenxa yalokho, i-Cf/AFS ikhombisa ukwakheka kwembotshana okufana kakhulu kanye nezimbotshana ezinokukhubazeka okumbalwa uma kuqhathaniswa ne-AFS.

3.5. Izakhiwo zemishini

Amajika okucindezela okucindezelayo kwe-Cf/AFS kanye ne-AFS acishe abe ne-porosity efanayo (83.2% kanye nama-81.4%, ngokulandelana) ethulwa ku-Umdwebo 9(a). Ijika elicindezelayo le-stress-strain libonisa isici sezigaba ezintathu, esihlanganisa indawo enwebekayo eqondile, isifunda se-plateau, kanye nesifunda sokuminyana. Amandla okukhiqiza acindezelayo e-AFS kanye ne-CF/AFS ayengu-8.44 MPa kanye no-11.87 MPa, ngokulandelana. Amandla okukhiqiza acindezelayo e-Cf/AFS anyuke ngo-40.6% uma kuqhathaniswa ne-AFS. Ngaleso sikhathi, amandla okumunca amandla e-Cf/AFS angcono kunalawo e-AFS ngohlobo olufanayo, njengoba kukhonjisiweUmdwebo 9(b). Amandla okumunca amandla e-AFS kanye ne-Cf/AFS cishe angu-3.3 MJ/m3 kanye no-6.1 MJ/m3, ngokulandelanayo. Umthamo wokumunca amandla we-Cf/AFS uthuthuke ngo-84.8% uma uqhathaniswa ne-AFS.

Umdwebo 9.Amajika esitimela sokucindezeleka okucindezelayo kanye namajika amandla okumunca amandla we-Cf/AFS kanye ne-AFS: (a) amajika esitimela esicindezelayo; (b) amajika amandla okumunca.

Ukufakwa kwe-Cf kuthuthukise kakhulu izakhiwo zemishini ze-foam core. Kuyaziwa ukuthi izakhiwo zemishini yei-aluminium foamzihlobene eduze nesakhiwo se-pore kanye nezakhiwo zemishini ye-strut. Ukuhlaziywa kwe-Macrostructural kubonise ukuthi ukungezwa kwe-Cf kucwengisise usayizi we-pore, ukusabalalisa kwe-pore okuthuthukisiwe, nokunciphisa ukukhubazeka kwezimbotshana. Okufana nokutholwe nguSasikumar et al. kanye neYangetal. Imbotshana encane ububanzi kanye nokusatshalaliswa kwembotshana ewumngcingo kuzuzisa kakhulu ukukhulisa amandla acindezelayo kanye nokumuncwa kahle kwamandla. Ngaphezu kwalokho, umphumela we-microstructure kuzakhiwo zemishini zegwebu ikakhulukazi ngenxa ye-CF eshumekwe ezindongeni ze-pore zegwebu. Ukusatshalaliswa nokuhlakazwa kwe-copper-coated of the carbon fibers ku-aluminium matrix kungafinyelela isibopho esiqinile phakathi kwamafayibha kanye ne-aluminium matrix, enomthelela ekudlulisweni komthwalo. I-modulus carbon fiber ephezulu egxilwe odongeni lwama-pore ingakhawulela ukuwohloka kodonga lwembotshana ngaphansi komthwalo wokucindezelwa futhi ithuthukise umthamo wokuthwala umthwalo. Zonke lezi zici zivuna i-Cf/AFS ukuthi ithole amandla esivuno esiphezulu namandla okumunca amandla uma kuqhathaniswa ne-AFS.

4. Iziphetho

I-CF/AFS kanye ne-AFS zalungiswa ngendlela yokupakisha ye-powder metallurgy kulo msebenzi. Ukuziphatha okunegwebu kwe-Cf/AFS kanye ne-AFS kwabonwa ngokuguquguqukayo ngemisebe ye-synchrotron ukuze

phenya ithonya le-C ku-nucleation yebhamuza nokukhula. Ngaphezu kwalokho, i-Cf ku-pore morphology, ukusatshalaliswa kwezimbotshana, kanye nezakhiwo zokucindezelwa kwamagwebu e-aluminium kwahlaziywa kahle. Iziphetho eziyinhloko yilezi:

(1) Ukuhlolwa kwemisebe ye-synchrotron endaweni yembula ukuthi kokubili izinqubo zokugwebu ze-Cf/AFS kanye ne-AFS zibonisa izigaba ezintathu ezihlukene: i-nucleation yebhamuza, ukukhula kwebhamuza nokuhlanganisa, nokuqina.

Uma kuqhathaniswa ne-AFS, inqubo yogwebu ye-Cf/AFS ibonisa ukuzinza okuphezulu nokufana kwebhamuza. I-AFS ijwayele ukwenza izimbotshana ezinkulu ngokungavamile nezimahhadla ngesikhathi senqubo yokuvela kwezimbotshana. Ukwengeza, ukungalingani kubangelwa umphumela we-nucleation we-Cf, ovimbela ukuqhekeka kodonga lwebhamuza futhi wehlise ukuhlangana ngenkathi ukhulisa izinga le-nucleation.

(2) Ukwengezwa kwe-0.5 wt.% Cf kuthuthukisa imbobo elingana nobubanzi ukusuka ku-2.9 ± 0.2 mm kuya ku-1.9 ± 0.1 mm, kunciphisa ngokuphawulekayo ukukhubazeka kwama-pore. Ngesikhathi esifanayo, i-microstructure iveza ukumanzisa okuhle kwe-Cf, esabalaliswa eduze kodonga lwezimbotshana kanye nesixhumi esibonakalayo esiqinile segesi, ngaleyo ndlela ithuthukisa ukuqina kwegwebu.

(3) Uma kuqhathaniswa ne-AFS, amandla okukhiqiza okucindezelayo namandla okumunca amandla e-Cf/AFS akhuphuke cishe ngo-40.6% no-84.8%, ngokulandelana. Okutholwe kulolu cwaningo kunganikeza imibono yokuqiniswa kwamaphaneli esamishi ye-aluminium Foam anezixhumanisi ze-metallurgical bonding ezinamandla okusebenzisa ubunjiniyela emkhakheni wezimboni zezimoto kanye ne-aerospace.

I-athikili evela kuJournal of Materials Research and Technology