Puas yog titanium sib dua li txhuas?
Hauv kev sib piv cov khoom siv hlau, qhov ntom ntom feem ntau suav hais tias yog qhov ntsuas tseem ceeb ntawm "lightness" lossis "heaviness." Thaum titanium thiab txhuas, ob qho tib si siv dav hlau, sib ntsib, ib qho kev xav tsis zoo tshwm sim: ntau tus neeg xav tias titanium yog sib dua li txhuas tsuas yog vim lo lus "lub teeb" hauv lawv cov npe. Txawm li cas los xij, cov ntaub ntawv tshawb fawb qhia tawm qhov sib txawv ntawm -titanium qhov ceev yog kwv yees li 4.51 g / cm³, thaum aluminium qhov ntom tsuas yog 2.7 g / cm³, lub ntsiab lus titanium tiag tiag txog 1.67 npaug hnyav dua li txhuas. Qhov kev txiav txim siab tsis txaus ntseeg no tsis yog tsuas yog cuam tshuam cov kev nkag siab zoo xwb tab sis tseem cuam tshuam rau kev xaiv cov khoom siv thiab kev tsim qauv.
Titanium tus yam ntxwv ntom ntom tshwm sim los ntawm qhov tshwj xeeb ntawm nws cov qauv atomic thiab cov khoom siv tshuaj lom neeg. Raws li cov khoom naj npawb 22, titanium atoms muaj 22 protons thiab 22 electrons, tsim ib qho kev ruaj khov hexagonal siv lead ua qauv nrog muaj zog interatomic bonds, uas ua rau muaj concentrated loj hauv ib chav tsev ntim. Nyob rau hauv sib piv, txhuas atoms (atomic tooj 13) muaj ib tug looser electron configuration, tsim ib tug cubic siv lead ua qauv nrog loj inter- atomic gaps, uas ua rau ib tug txo nyob rau hauv ib chav tsev ntim. Qhov no atomic - theem sib txawv yog qhia ncaj qha nyob rau hauv qhov ceev qhov tseem ceeb: titanium qhov ntom yog ze li ntawm 57% ntawm cov hlau, thaum txhuas yog li ntawm 30%. Yog hais tias ob qho tib si tau ua rau hauv cubes ntawm tib lub ntim, titanium thaiv yuav hnyav dua li txhuas thaiv. Cov yam ntxwv no yog qhov tseem ceeb tshwj xeeb tshaj yog nyob rau hauv aerospace teb- engineers yuav tsum tau ua kom meej xam qhov cuam tshuam ntawm txhua gram ntawm qhov hnyav ntawm aircraft roj efficiency.
Txawm hais tias titanium hnyav dua li txhuas, nws lub zog tshwj xeeb (qhov piv ntawm lub zog rau qhov ntom ntom) ua rau muaj txiaj ntsig zoo heev. Piv txwv li, feem ntau Ti-6Al-4V titanium alloy muaj lub zog tensile tshaj 1000 MPa, thaum lub zog tensile ntawm 6061 aluminium alloy feem ntau nyob ib ncig ntawm 300 MPa. Tom qab xam lub zog tshwj xeeb, titanium alloy tus nqi yog 1.3 npaug ntawm aluminium alloy. Qhov no txhais tau hais tias titanium alloy structural Cheebtsam tuaj yeem tsim kom sib dua thiab nyias dua thaum coj tus nqi tib yam. Lub Boeing 787 Dreamliner yog ib qho piv txwv zoo: nws lub fuselage feem ntau siv cov titanium alloys es tsis txhob siv cov txhuas txhuas, ua tiav qhov hnyav los ntawm 15% thaum tswj cov txheej txheem, txhim kho roj kev lag luam. Tsis tas li ntawd, titanium alloys muaj qhov zoo dua corrosion kuj piv rau txhuas, tshwj xeeb tshaj yog nyob rau hauv marine ib puag ncig. Thaum txhuas tau yooj yim tsim cov txheej txheem alumina, kev sib cuag nrog cov tshuaj chloride ions ntev tuaj yeem ua rau pitting corrosion. Titanium, ntawm qhov tod tes, corrodes tsuas yog 1/10 tus nqi ntawm txhuas hauv dej hiav txwv, ua rau nws nyiam cov khoom siv rau kev tsim nkoj.
Aluminium lub teeb yuag kom zoo dua kuj yog qhov hloov tsis tau hauv cov xwm txheej tshwj xeeb. Hauv cov neeg siv khoom siv hluav taws xob, cov xov tooj ntawm tes siv 7075 txhuas alloy (qhov ntom 2.8 g / cm³) es tsis txhob siv cov titanium alloy, ua tau raws li cov qauv tsim muaj zog thaum tsis txhob muaj qhov hnyav ntxiv uas tuaj yeem cuam tshuam tsis zoo rau kev tuav. Hauv kev lag luam automotive, aluminium alloy log (qhov ceev 2.7 g / cm³) yog 40% sib dua li cov hlau log, txo qhov tsis muaj zog thiab txhim kho kev ua haujlwm; thaum titanium alloy log muaj zog dua, lawv cov nqi siab thiab tsis muaj qhov hnyav hnyav kom zoo dua txwv lawv txoj kev siv, txwv lawv daim ntawv thov kom muaj qhov tsawg hauv siab -kawg tsheb sib tw. Tsis tas li ntawd, txhuas cov hluav taws xob conductivity (35% IACS) yog qhov zoo tshaj rau titanium's (3.1% IACS), ua rau nws yog cov khoom siv tseem ceeb hauv kev xa hluav taws xob{10}} siab- cov kab xa hluav taws xob siv cov khoom siv hluav taws xob txhuas los xyuas kom muaj kev ua tau zoo thaum txo ntauwd load.
Qhov tseem ceeb ntawm kev xaiv cov khoom yog nyob rau hauv kev sib npaug ntawm kev ua tau zoo thiab tus nqi. Thaum titanium alloys khav theeb lub zog tshwj xeeb thiab kev tiv thaiv corrosion, lawv txoj kev ua haujlwm nyuaj thiab tus nqi siab (kwv yees li 5-10 npaug ntawm cov aluminium alloys) txwv lawv txoj kev siv dav hauv kev siv pej xeem. Aluminium alloys, ntawm qhov tod tes, leverage mature processing techniques and low cost to become the second most consumed metal worldly (tom qab steel). Nyob rau hauv lub neej yav tom ntej, nrog rau kev loj hlob ntawm additive manufacturing technology, tus nqi ntawm customized zus tau tej cov titanium alloys yuav tsum tau txo, ua rau ib tug txuas ntxiv nthuav ntawm lawv cov lag luam koom nyob rau hauv kev kho mob cog thiab high-end khoom ua si. Lub caij no, aluminium alloys, los ntawm microalloying thiab kev kho cua sov kom zoo, tuaj yeem txhim kho lawv lub zog thiab kev tiv thaiv corrosion, sib sau lawv txoj haujlwm hauv kev thauj mus los, kev tsim kho, thiab lwm yam.
Qhov kev sib cav "lub teeb piv rau qhov hnyav" kev sib cav ntawm titanium thiab aluminium yog qhov tseem ceeb ntawm kev sib txuam ntawm qhov ntom, lub zog, tus nqi, thiab kev ua haujlwm hauv cov ntaub ntawv tshawb fawb. Titanium, with its higher density, achieves superior specific strength and corrosion resistance, becoming a "hidden champion" in high-end manufacturing; aluminium, nrog nws qhov hnyav hnyav thiab kev lag luam zoo, txhawb nqa lub tshuab loj ntawm kev lag luam niaj hnub. Kev nkag siab qhov sib txawv no tsis tsuas yog pab peb xaiv cov khoom siv muaj txiaj ntsig ntau dua, tab sis kuj tso cai rau peb pom tias kev txhim kho thev naus laus zis hloov kho thaj chaw muaj kev lag luam ntawm macrocosm los ntawm microscopic kev npaj ntawm atoms. Ntawm txoj kev ntawm cov khoom siv tshiab, tsis muaj qhov "zoo" lossis "phem," tsuas yog cov kev daws teeb meem zoo tsim nyog rau cov xwm txheej tshwj xeeb.
