Yog koj impression ntawmtitaniumtxwv tsis pub nws yog "lub teeb, tawv, xeb-pov thawj qhov chaw-hnub nyoog hlau"-lossis tej zaum yog "biocompatible hlau" siv rau kev cog hniav-ces qhov kev xav uas kuv tab tom qhia hnub no tuaj yeem xav tsis thoob: titanium yog, qhov tseeb, kuj yog superconductor.
Hais lus nruj me ntsis, ntshiab titanium tiag tiag nkag mus rau hauv lub xeev superconducting ntawm qhov kub tsis tshua muaj siab. Txawm li cas los xij, nws yuav yog qhov yuam kev loj los xav tias qhov no txhais tau tias titanium tuaj yeem siv los tsim cov tshuab maglev lossis MRI tshuab. Zaj dab neeg ntawm titanium raws li ib tug superconductor yog ntau dua ntawm ib daim ntawm scientific trivia-theoretically siv tau, tab sis siv tsis tau. Nyob rau hauv kev muaj tiag, nws yog titanium lub luag hauj lwm raws li ib tug alloying caij uas tiag tiag underpins lub superconducting kev lag luam.
Lub Superconducting Threshold ntawm Ntshiab Titanium: 0.4 K-Txawm tias xav tau ntau dua li cov hluav taws xob hauv qab cosmic. Yuav pib nrog qhov xaus: ntshiab titanium yog qhov tseeb superconducting, tab sis nws qhov kub thiab txias tseem ceeb yog pitifully tsawg-uas yog hais tias, qhov pib nkag mus rau lub xeev superconducting yog dauntingly siab. Nws yuav tsum tau txias hauv qab 0.5 K kom ua tiav superconductivity; Qhov ntsuas kub no nce mus txog qhov txwv tsis pub dhau ntawm qhov tuaj yeem ncav cuag los ntawm kev txo qis ntawm cov kua helium, ua rau nws ob qho tib si txwv tsis pub kim thiab tsis muaj txiaj ntsig los ntawm kev xav engineering. Tshwj xeeb, qhov tseem ceeb ntawm superconducting kub ntawm cov ntshiab titanium yog kwv yees li 0.42 K, nrog rau qhov tseem ceeb sib nqus ntawm tsuas yog 58 gauss.
Yog li ntawd, yog tias koj yuav tsum tau thov tias "titanium yog ib qho khoom siv zoo tshaj plaws," tus kws kho mob nruj yuav zoo li frown. Lub superconductivity ntawm ntshiab titanium yog to taub zoo dua raws li ib qho kev kawm nyob rau hauv condensed teeb meem physics es tsis yog ib tug siv tau rau kev siv engineering.
Qhov tseeb protagonist yog "niobium doped nrog titanium"-los yog, ntau precisely, lub niobium-titanium (Nb-Ti) alloy. Nyob rau hauv lub realm ntawm superconductivity, titanium tus nqi tiag tiag tsis yog nyob rau hauv ua yeeb yam ib leeg, tab sis nyob rau hauv kev pab raws li ib tug "txhawb neeg uas ua ntawv" rau niobium. Niobium-titanium alloys tam sim no yog cov khoom siv dav siv tshaj plaws. Lawv muaj cov cuab yeej ua haujlwm zoo heev, tso cai rau lawv ua tiav rau hauv cov xov hlau zoo ntawm cov txheej txheem extrusion thiab kos duab. Qhov no ua rau lawv zoo tagnrho rau kev tsim cov hlau nplaum superconducting uas ua haujlwm nyob rau hauv thaj chaw sib nqus ntawm 2 txog 10 teslas-ib lub peev xwm ua haujlwm hnyav rau kev siv cov coils superconducting siv hauv magnetic resonance imaging (MRI) systems. Hauv cov alloys no, cov ntsiab lus titanium tuaj yeem ua tau zoo heev ntawm 45% mus rau 59% hauv ntau yam kev tshawb fawb-nrog rau lub hom phiaj ntawm kev ua kom zoo dua qhov tseem ceeb tam sim no thaum txo cov nqi.
Qhov no yog qhov muaj tseeb tiag ntawm cov ntaub ntawv tshawb fawb: cov khoom siv hlau zoo tshaj plaws tsis yog qhov ua tau zoo tshaj plaws. Ntshiab titanium muaj qhov ntsuas kub ntawm qhov tseem ceeb ntawm 0.42 K-tso nws ze rau hauv qab ntawm cov khoom siv superconducting. Txawm li cas los xij, thaum titanium tsis muab nws qhov tseem ceeb los ntawm superconductivity, thaj chaw ntawm superconductivity tau dhau los ua tus pheej yig dua thiab ua haujlwm tau zoo vim yog kev koom tes ntawm titanium. Niobium-titanium alloys underpin cov hlau nplaum nyob hauv ntau txhiab lub tshuab MRI thoob ntiaj teb thiab ua kom cov khoom siv accelerators ua haujlwm ntawm qib siab zog. Qee zaum, ua "ua haujlwm" yog qhov tseem ceeb dua li "dawb huv."
