Cov kav dej tooj liab yog ib qho nyuaj thiab tsis yooj yim rau corrode.
Lawv kuj tseem tiv taus qhov kub thiab txias thiab kev kub ntxhov thiab tuaj yeem siv rau ntau qhov chaw. Hauv kev sib piv, qhov tsis zoo ntawm ntau lwm cov kav dej yog pom tseeb. Piv txwv li, galvanized steel kav, uas feem ntau siv nyob rau hauv cov tsev nyob yav dhau los, yog yooj yim heev rau xeb. Tom qab siv sijhawm luv luv, cov kais dej yuav tig daj thiab cov dej ntws yuav txo qis. Qee cov ntaub ntawv yuav txo tau lawv lub zog sai ntawm qhov kub thiab txias, uas yuav ua rau muaj kev phom sij tsis zoo thaum siv cov kav dej kub. Txawm li cas los xij, qhov kub ntawm cov tooj liab yog siab li 1083 degrees Celsius, thiab qhov kub ntawm cov dej kub tsis zoo rau cov kav dej tooj liab. Cov kws tshawb fawb tshawb fawb tau tshawb pom cov kav dej tooj liab hnub rov qab 4,500 xyoo hauv Egyptian pyramids, uas tseem siv niaj hnub no.
Cov kav dej tooj liab yog cov kav ntev
Cov khoom siv tshuaj lom neeg ntawm tooj liab yog qhov ruaj khov, thiab nws ua ke cov yam ntxwv ntawm kev ua haujlwm txias, kub tsis kam, siab tsis kam, corrosion kuj thiab hluav taws kub tsis kam (tooj liab muaj qhov melting point txog 1083 degrees Celsius), thiab tuaj yeem siv tau ntev. nyob rau hauv ib puag ncig sib txawv. Lub neej kev pab cuam ntawm cov kav dej tooj liab tuaj yeem ntev npaum li lub neej ntawm lub tsev, lossis ntev dua. Piv txwv li, cov kav dej tooj liab tau teeb tsa hauv Peking Union Medical College Tsev Kho Mob hauv xyoo 1920s tau zoo rau ntau tshaj 70 xyoo. Nws tuaj yeem pom tau tias cov kav dej tooj liab yog cov kav dej uas tau sim ua tiav los ntawm ntau tshaj li ib puas xyoo ntawm lub sijhawm thiab kev ua haujlwm.
Cov kav dej tooj liab muaj kev nyab xeeb thiab txhim khu kev qha
Cov kav dej tooj liab sib xyaw ua ke qhov zoo ntawm cov kav hlau hlau thiab cov kav dej tsis yog hlau. Nws yog ib qho nyuaj tshaj li cov kav dej yas thiab muaj lub zog siab ntawm cov hlau dav dav (lub zog ntawm cov kav dej txias txias yog sib npaug rau cov kav hlau steel nrog tib lub phab ntsa tuab); Nws yog qhov yooj yim rau khoov dua li cov hlau dav dav, muaj qhov zoo toughness thiab siab ductility, thiab muaj kev co zoo heev, cuam tshuam tsis kam thiab Frost heave kuj.
Cov kav dej tooj liab tuaj yeem tiv taus qhov txias txias thiab kub kub, nrog rau ntau yam kev siv los ntawm -196 degrees mus rau 250 degrees, thiab tuaj yeem hloov kho qhov kub thiab txias (-high temperature-low temperature-high temperature-), thiab kev ua haujlwm. yuav tsis raug txo vim kev siv mus sij hawm ntev thiab kub hloov pauv, thiab yuav tsis tsim kev laus. Qhov no yog dhau qhov ncav cuag ntawm cov kav dej zoo tib yam.
Lub linear expansion coefficient ntawm tooj liab kav yog me me, uas yog 1/10 ntawm cov yas kav, thiab nws yog qaug zog-resistant. Thaum qhov kub thiab txias hloov, yuav tsis muaj ntau thermal expansion thiab contraction, uas yuav ua rau muaj kev ntxhov siab qaug zog tawg.
Cov yam ntxwv no ua rau daim ntawv thov ntawm cov kav dej tooj liab hauv qhov chaw txias tau zoo heev. Hauv cov cheeb tsam txias heev, qhov kub thiab txias sib txawv ntawm thaum sawv ntxov thiab yav tsaus ntuj yog qhov loj. Cov kav dej ib txwm muaj cov kab sib txuas loj loj thiab tsis muaj zog, uas ua rau muaj kev ntxhov siab qaug zog tawg los ntawm thermal expansion thiab contraction. Qee cov kav dej tau lees tias tsis yog nkig ntawm -20 degrees, tab sis qhov tseeb lawv tsis tuaj yeem tiv taus kev ua haujlwm siab thiab muaj lub neej ua haujlwm luv luv, uas tsis muaj qhov tseem ceeb. Txawm hais tias kev ntsuas rwb thaiv tsev tuaj yeem siv tau, nws yog ib qho nyuaj kom tsis txhob muaj qhov kub thiab txias thaum lub sij hawm kev thauj mus los, kev cia thiab kev teeb tsa. Kev ua haujlwm ntawm cov kav dej tooj liab ntawm -183 degrees yog tib yam li ntawm chav tsev kub.
