Nyowani tungsten alloys ari kuvandudzwa muSchuh Boka kuMIT anogona kutsiva yapera uranium muzvombo-kubaya projectiles. Wegore rechina wezvidzidzo zvesainzi uye mudzidzi akapedza kudzidza weinjiniya Zachary C. Cordero ari kushandira pane yakaderera-chepfu, yakakwirira-simba, yakakwirira-density zvinhu zvekutsiva uranium yapera mumabasa echiuto. Uranium yakapera inokonzeresa njodzi yehutano kumasoja nevanhuwo zvavo. "Ndicho chikonzero chekuyedza kutsiva," anodaro Cordero.

Tungsten yakajairika yaizoita howa kana kubvongodza pakukanganisa, kuita kwakaipisisa kunogoneka. Saka chinonetsa ndechekugadzira alloy inokwanisa kuenderana nekuita kweuranium yapera, inova inorodza yega apo inogera kubva pazvinhu uye inochengetedza mhino yakapinza painopinza-chinangwa interface. "Tungsten pachayo yakasimba uye yakaoma. Isu tinoisa mune mamwe maalloying zvinhu kuti tigadzire kuti tigone kuibatanidza muchinhu ichi chakawanda, ”anodaro Cordero.

Tungsten alloy ine chromium nesimbi (W-7Cr-9Fe) yakanga yakasimba zvakanyanya kudarika kutengeserana tungsten alloys, Cordero yakashuma mubepa rine munyori mukuru uye weDhipatimendi reZvinhu Sainzi neUinjiniya mukuru Christopher A. Schuh nevamwe vaaishanda navo mupepanhau Metallurgical and Materials. Transactions A. Kuvandudzwa kwakavepo kuburikidza nekugadzirisa hupfu hwesimbi mumuchina-unobatsira sintering inopisa muchina, nemigumisiro yakanakisisa, yakayerwa nekugadzirwa kwezviyo zvakanaka uye kuoma kwepamusoro, kunowanikwa panguva yekugadzirisa kweminiti imwe pa 1,200 degrees Celsius. Nguva refu yekugadzirisa uye tembiricha yakakwira zvakakonzera kukora zviyo uye kuita kushoma kwemuchina. Vamwe vanyori vaisanganisira MIT engineering uye zvinhu zvesainzi mudzidzi Mansoo Park, Oak Ridge postdoctoral mumwe Emily L. Huskins, Boise State Associate Purofesa Megan Frary uye mudzidzi akapedza kudzidza Steven Livers, uye Army Research Laboratory mechanical engineer uye mutungamiri wechikwata Brian E. Schuster. Sub-scale ballistic miedzo ye tungsten-chromium-iron alloy yakaitwa zvakare.

"Kana iwe uchikwanisa kugadzira nanostructured kana amorphous bulk tungsten (alloy), inofanirwa kunge iri yakanakira ballistic zvinhu," Cordero anodaro. Cordero, chizvarwa cheBridgewater, NJ, akagamuchira National Defence Science uye Engineering (NDSEG) Fellowship muna 2012 kuburikidza neAir Force Office yeScientific Research. Tsvagiridzo yake inotsigirwa neUS Defense Threat Reduction Agency.

Ultrafine zviyo chimiro

“Magadzirirwo andinoita zvinhu zvangu ndeehupfu apo tinotanga tagadzira nanocrystalline poda tozoibatanidza kuita chinhu chakawanda. Asi dambudziko nderekuti kubatanidzwa kunoda kufumura zvinhu kune tembiricha yakakwira, ”anodaro Cordero. Kupisa ma alloys kusvika pakupisa kwakanyanya kunogona kukonzera zviyo, kana kuti makristasi ega ega, mukati mesimbi kuwedzera, izvo zvinovaderedza. Cordero yakakwanisa kuwana ultrafine zviyo chimiro cheanenge 130 nanometers muW-7Cr-9Fe compact, yakasimbiswa neelectron micrographs. “Tichishandisa nzira iyi yekugadzira hupfu, tinogona kugadzira masamples makuru anosvika masendimita maviri mudhayamita, kana kuti tinogona kukwira, tiine masimba ekumanikidza e4 GPa (gigapascals). Iyo nyaya yekuti isu tinogona kugadzira zvinhu izvi tichishandisa scalable process inogona kutonyanya kushamisa, ”anodaro Cordero.

“Zvatiri kuedza kuita seboka kugadzira zvinhu zvakawanda nemananostructures akanaka. Chikonzero chatinoda kudaro ndechekuti zvinhu izvi zvine zvinhu zvinofadza izvo zvinogona kushandiswa mumashandisirwo mazhinji, ”anowedzera Cordero.

Haiwanikwi mune zvakasikwa

Cordero akaongororawo kusimba kwesimbi alloy poda ine nanoscale microstructures mune Acta Materialia rejenari bepa. Cordero, aine munyori mukuru Schuh, akashandisa ese macomputitional simulations uye murabhoritari kuyedza kuratidza kuti alloys esimbi senge tungsten uye chromium ane akafanana ekutanga simba aiwanzoita homogenize uye kugadzira yakasimba yekupedzisira chigadzirwa, nepo kusanganiswa kwesimbi dzine simba rekutanga risingaenderane. sezvo tungsten uye zirconium zvaida kuburitsa alloy isina simba ine inopfuura chikamu chimwe chiripo.

"Maitirwo ekugadzira bhora rine simba repamusoro-soro mumwe muenzaniso wemhuri yakakura yemaitirwo ayo iwe unoshandura heck kunze kwezvinhu kutyaira microstructure yayo kuita isinganzwisisike isina kuenzana mamiriro. Iko hakuna yakanaka sisitimu yekufungidzira iyo microstructure inobuda, saka nguva zhinji uku kuyedza uye kukanganisa. Isu takanga tichiedza kubvisa empiricism kubva mukugadzira alloys anozogadzira metastable yakasimba mhinduro, unova mumwe muenzaniso wechikamu chisina kuenzana, "Cordero anotsanangura.

"Iwe unogadzira idzi dzisiri-yakaenzana nhanho, zvinhu zvawaisazowanzoona munyika yakakupoteredza, muzvisikwa, uchishandisa aya akanyanyisa maitiro ekuchinja," anodaro. Maitiro ekugaya bhora repamusoro-simba anosanganisira kudzokororwa kugerwa kwehupfu hwesimbi nekuveura kutyaira izvo zvinosanganisa zvinhu kuti zvisanganise panguva yekukwikwidza, maitiro ekudzoreredza anoitwa nemhepo anobvumira iyo alloy kuti idzokere kune yayo yakaenzana mamiriro, ayo muzviitiko zvakawanda ndeyekuparadzanisa. . "Saka pane makwikwi aya pakati pemaitiro maviri aya," Cordero anotsanangura. Bepa rake rakakurudzira muenzaniso wakapfava wekufanotaura makemikari mune yakapihwa alloy iyo inozogadzira yakasimba mhinduro uye nekuisimbisa nemiedzo. "Iyo yakagayiwa hupfu ndedzimwe simbi dzakaomarara dzakaonekwa nevanhu," Cordero anodaro, achicherekedza bvunzo dzakaratidza tungsten-chromium alloy ine nanoindentation kuomarara kwe21 GPa. Izvi zvinovaita zvakapetwa kaviri kuomarara kwenanoindentation kwenanocrystalline iron-based alloys kana coarse-grained tungsten.

Metallurgy inoda kuchinjika

Mune ultrafine tsanga tungsten-chromium-iron alloy compacts akadzidza, alloys akanhonga simbi kubva abrasion simbi inokuya midhiya uye vial panguva yakakwirira-simba bhora kugaya. "Asi zvinozoitika izvo zvinogona zvakare kuve chinhu chakanaka, nekuti chinoita senge chinomhanyisa densification pakudziya kwakadzika, izvo zvinoderedza huwandu hwenguva yaunofanirwa kushandisa pane iyo tembiricha yepamusoro inogona kutungamira kune yakaipa shanduko mumicrostructure," Cordero anotsanangura. "Chinhu chikuru kuve kuchinjika uye nekuziva mikana mumetallurgy."

A compacted metal alloy pellet inogara padivi pe as-milled tungsten-chromium iron metal powders muchikepe chinoshandiswa kuyera simbi. Mabhora esimbi anoshandiswa kukanganisa simbi muguyo rebhora repamusoro-simba. Chikwereti: Denis Paiste/Materials Processing Center
Cordero akapedza kudzidza kubva kuMIT muna 2010 aine bachelor's mufizikisi uye akashanda kwegore kuLawrence Berkeley National Lab. Ikoko, akafemerwa nevashandi veinjiniya vakadzidza kubva kuchizvarwa chekare chemetallurgists vakagadzira crucibles kuti abate plutonium yeManhattan Project munguva yeHondo Yenyika II. “Kunzwa rudzi rwezvinhu zvavakanga vachishandira kwakandifadza zvikuru uye kuda kugadzira simbi. Zvinongonakidzawo,” anodaro Cordero. Mune zvimwe zvinyorwa zvesainzi, anoti, “Hausvike pakuvhura choto pa1,000 C, woona chimwe chinhu chinopenya chitsvuku chinopisa. Iwe hausvike pazvinhu zvinopisa kupisa. " Anotarisira kupedza PhD yake muna 2015.

Kunyangwe basa rake razvino rakanangana nemaitiro ekushandisa, rudzi rwehupfu hwaari kuita hunoshandiswawo kugadzira magineti. "Ruzivo rwakawanda uye ruzivo runogona kushandiswa kune zvimwe zvinhu," anodaro. "Kunyangwe ichi chiri chinyakare chesimbi, unogona kuisa iyi simbi yechikoro chekare kune zvitsva zvechikoro."