Ama-alloys amasha e-tungsten athuthukiswa ku-Schuh Group e-MIT angase athathe indawo ye-uranium ephelile kuma-projectiles okubhoboza izikhali. Umfundi owenza unyaka wesine wesayensi yezinto zokwakha kanye nobunjiniyela u-Zachary C. Cordero usebenza ngezinto ezinobuthi obuphansi, amandla aphezulu, nokuminyana okuphezulu esikhundleni se-uranium esiphelile ekusetshenzisweni kwezempi kwesakhiwo. Ukwehliswa kwe-uranium kubangela ingozi engaba yingozi empilweni kumasosha kanye nezakhamuzi. "Leso yisizathu sokuzama ukuyifaka esikhundleni," kusho uCordero.

I-tungsten evamile izoba ngamakhowe noma ibe buthuntu kumthelela, ukusebenza okubi kakhulu okungenzeka. Ngakho-ke inselele iwukwenza ingxubevange engakwazi ukuhambisana nokusebenza kwe-uranium ephelile, ezilola yona njengoba igunda impahla futhi igcine ikhala elicijile endaweni okuhloswe ngayo ukungena. “I-Tungsten iyodwa inamandla ngendlela emangalisayo futhi ilukhuni. Sifaka ezinye izinto ze-alloying ukuze sikwenze ukuze sikwazi ukukuhlanganisa kule nto ngobuningi, ”kusho uCordero.

Ingxubevange ye-tungsten ene-chromium ne-iron (W-7Cr-9Fe) yayinamandla kakhulu kunama-tungsten alloys ezohwebo, kubika i-Cordero ephepheni elinombhali ophezulu kanye nenhloko yoMnyango Wezesayensi Yezinto Nezobunjiniyela uChristopher A. Schuh kanye nozakwabo kujenali ye-Metallurgical and Materials Okwenziwayo A. Ukuthuthukiswa kwafinyelelwa ngokuhlanganisa izimpushana zensimbi emshinini wokunyathelisa oshisayo we-sintering osizwa umkhakha, nomphumela omuhle kakhulu, ukalwa ngesakhiwo sokusanhlamvu esihle kanye nokuba lukhuni okuphezulu kakhulu, okutholwe ngesikhathi sokucubungula esiyiminithi elingu-1 ku-1,200 degrees Celsius. Izikhathi ezinde zokucubungula kanye namazinga okushisa aphezulu kuholele ezinhlamvini ezimahhadla nokusebenza komshini okubuthakathaka. Ababhali ababambisene nabo bahlanganisa umfundi oneziqu ze-MIT zobunjiniyela nesayensi yezinto zokwakha, uMansoo Park, u-Oak Ridge ozakwabo ngemuva kokuthola ubudokotela u-Emily L. Huskins, Uprofesa Wesifunda sase-Boise u-Megan Frary kanye nomfundi oneziqu u-Steven Livers, kanye nonjiniyela wemishini we-Army Research Laboratory kanye nomholi weqembu u-Brian E. Schuster. Ukuhlolwa kwesikali se-ballistic ye-tungsten-chromium-iron alloy nakho kwenziwe.

"Uma ungenza i-nanostructured noma i-amorphous bulk tungsten (ingxubevange), kufanele ibe yinto efanelekile ye-ballistic," kusho u-Cordero. UCordero, ongowokuzalwa eBridgewater, NJ, uthole iNational Defence Science and Engineering (NDSEG) Fellowship ngo-2012 ngeHhovisi Lasemoyeni Lokucwaninga Kwesayensi. Ucwaningo lwakhe luxhaswe yi-US Defence Threat Reduction Agency.

Ultrafine okusanhlamvu isakhiwo

“Indlela engenza ngayo izinto zami nge-powder processing lapho siqale senza i-nanocrystalline powder bese siyihlanganisa ibe into eyinqwaba. Kepha inselelo ukuthi ukuhlanganiswa kudinga ukuveza izinto emazingeni okushisa aphezulu, ”kusho uCordero. Ukushisa ama-alloys emazingeni okushisa aphezulu kungabangela okusanhlamvu, noma izizinda ze-crystalline ngazinye, ngaphakathi kwensimbi ukuba zikhule, okuwenza buthaka. I-Cordero ikwazile ukuzuza ukwakheka kokusanhlamvu kwe-ultrafine okungaba ama-nanometer angu-130 ku-W-7Cr-9Fe compact, okuqinisekiswe ama-electron micrographs. “Sisebenzisa lo mzila wokucutshungulwa kwempushana, singenza amasampula amakhulu afinyelela kumasentimitha angu-2 ububanzi, noma singaba sikhulu, ngamandla ashukumisayo acindezelayo angu-4 GPa (gigapascals). Iqiniso lokuthi singenza lezi zinto sisebenzisa inqubo engahlelekayo limangalisa kakhulu, ”kusho uCordero.

“Esizama ukukwenza njengeqembu ukwenza izinto eziningi ngama-nanostructures amahle. Isizathu sokuthi sifuna lokho yingoba lezi zinto zinezinto ezithakazelisayo kakhulu ezingase zisetshenziswe ezinhlelweni eziningi, ”kwengeza u-Cordero.

Ayitholakali emvelweni

I-Cordero iphinde yahlola amandla ezimpushana zengxubevange yensimbi ezinama-nanoscale microstructures ephepheni lejenali ye-Acta Materialia. U-Cordero, nombhali omkhulu u-Schuh, basebenzise kokubili ukulingiswa kwekhompyutha nokuhlolwa kwelabhorethri ukukhombisa ukuthi ama-alloys ensimbi afana ne-tungsten ne-chromium enamandla afanayo okuqala ayevame ukuhlangana futhi akhiqize umkhiqizo wokugcina onamandla, kuyilapho izinhlanganisela zezinsimbi ezinamandla okuqala angafani nalokhu. njengoba i-tungsten ne-zirconium ijwayele ukukhiqiza ingxubevange ebuthakathaka enesigaba esingaphezu kwesisodwa.

“Inqubo yokugaywa kwebhola elinamandla amakhulu iyisibonelo esisodwa somndeni omkhulu wezinqubo lapho ugoba khona i-heck out of material ukuze uqhubele isakhiwo salo esincane sibe esimweni esingalingani kahle. Alukho uhlaka oluhle ngempela lokubikezela i-microstructure ephumayo, ngakho-ke ezikhathini eziningi lokhu kuwukuhlola namaphutha. Besizama ukususa i-empiricism ekuklameni ama-alloys azokwakha isisombululo esiqinile esine-metastable, okuyisibonelo esisodwa sesigaba sokungalingani," kuchaza u-Cordero.

“Ukhiqiza lezi zigaba ezingalingani, izinto obungeke ujwayele ukuzibona emhlabeni okuzungezile, emvelweni, usebenzisa lezi zinqubo zokuguga ngokwedlulele,” usho kanje. Inqubo yokugaya ibhola elinamandla amakhulu ihlanganisa ukugunda okuphindaphindiwe kwezimpushana zensimbi ngokugunda okushayela izakhi zengxubevange ukuba zihlangane ngenkathi kuncintisana, izinqubo zokutakula ezicushwe ngokushisa zivumela ingxubevange ukuthi ibuyele esimweni sayo sokulingana, okuthi ezimweni eziningi ihlukane ngokwehlukana. . "Ngakho-ke kukhona lo mncintiswano phakathi kwalezi zinqubo ezimbili," kuchaza u-Cordero. Iphepha lakhe lihlongoze imodeli elula yokubikezela amakhemikhali ku-alloy enikeziwe ezokwakha isisombululo esiqinile futhi iqinisekise ngokuhlolwa. "Ama-powder agayiwe angezinye zezinsimbi ezinzima kakhulu ezibonwe ngabantu," kusho u-Cordero, ephawula ukuhlolwa kubonise i-tungsten-chromium alloy inobulukhuni be-nanoindentation be-21 GPa. Lokho kubenza bacishe kabili ubulukhuni be-nanoindentation be-nanocrystalline iron-based alloys noma i-tungsten enamahlamvu.

I-Metallurgy idinga ukuguquguquka

Kumacwecwe engxubevange yensimbi ye-tungsten-chromium-iron acwaninga ngayo, ama-alloy acosha insimbi ekuhubheni komshini wokugaya insimbi kanye nebhodlela ngesikhathi sokugaya ibhola elinamandla amakhulu. "Kodwa kuvele ukuthi lokho nakho kungaba yinto enhle, ngoba kubukeka sengathi kusheshisa ukuminyana emazingeni okushisa aphansi, okunciphisa isikhathi okufanele usichithe kulawo mazinga okushisa aphezulu angaholela ekushintsheni okubi kwe-microstructure," Kuchaza uCordero. "Into enkulu wukuvumelana nezimo nokubona amathuba kwezensimbi."

I-alloy pellet yensimbi ehlanganisiwe ihlala eduze kwezimpushana zensimbi yensimbi ye-tungsten-chromium egayiwe esikebheni esisetshenziselwa ukukala izinsimbi. Amabhola ensimbi asetshenziselwa ukuguqula izinsimbi endaweni yokugaya yebhola enamandla kakhulu. Isikweletu: Denis Paiste/Materials Processing Center
U-Cordero uphothule i-MIT ngo-2010 eneziqu ze-physics futhi wasebenza unyaka e-Lawrence Berkeley National Lab. Lapho, wagqugquzelwa izisebenzi zonjiniyela ezafunda esizukulwaneni sangaphambili se-metallurgists abenza iziphambano ezikhethekile zokubamba i-plutonium ye-Manhattan Project phakathi neMpi Yezwe II. “Ukuzwa uhlobo lwezinto ababesebenza kuzo kwangijabulisa kakhulu futhi ngakuthanda kakhulu ukucubungula izinsimbi. Futhi kumnandi kakhulu, ”kusho uCordero. Kweminye imikhakha yesayensi yezinto zokwakha, uthi, “Awukwazi ukuvula isithando somlilo ngo-1,000 C, bese ubona okuthile okubenyezelayo okubomvu kushisa. Awuzitholi izinto ezibamba ukushisa.” Ulindele ukuqeda i-PhD yakhe ngo-2015.

Nakuba umsebenzi wakhe wamanje ugxile ekusetshenzisweni kwesakhiwo, uhlobo lokucutshungulwa kwempushana akwenzayo luphinde lusetshenziselwe ukwenza izinto kazibuthe. Uthi: “Ulwazi oluningi nolwazi lungasetshenziswa kwezinye izinto. “Yize lokhu kuwukusansimbi okujwayelekile kwesakhiwo, ungasebenzisa le nsimbi yesikole esidala ezintweni zesikole esisha.”