Qhov kev cuam tshuam zoo ntawm tooj liab nyob hauv keeb kwm ntawm tib neeg kev vam meej tsis tau txav los ntawm ib qho khoom siv. Tooj liab yog thawj cov khoom siv dav hlau, thiab nws lub luag haujlwm zoo heev uas nyob hauv keeb kwm ntawm tib neeg kev vam meej, muaj ob theem npe hu ua tom qab nws cov alloy: Cov Hnub Nyoog Bronze thiab Sub-Bronze Age. Niaj hnub no, tooj liab tseem yog qhov thib peb feem ntau siv hlau hauv ntiaj teb, thib ob rau cov hlau thiab txhuas. Yog tsis muaj tooj liab, lub neej niaj hnub yuav tsis txaus ntseeg. Los ntawm cov liaj teb ntawm kev lag luam, txhua yam khoom xav tau txhua hnub, kev ua kom zoo nkauj zoo nkauj thiab kos duab, kos duab tooj tau tuaj yeem piav qhia ubiquitous cov neeg ib puag ncig. Tsab xov xwm no txheeb xyuas kev lag luam tooj liab hauv kev nthuav dav los ntawm qhov kev xam pom ntawm cov ntxhia pob zeb, kev tsim khoom, kev noj, kev siv qis, kev cuam tshuam tus nqi, thiab lwm yam. Nws yog qhov khoom siv tsis tseem ceeb rau kev lag luam tooj liab.
Tooj liab yog ib tus hlau pom thaum ntxov tshaj plaws los ntawm noob neej, thiab yog ib qho zoo tshaj plaws hlau ntshiab. Nws yog qhov nyuaj me ntsis, tawv dhau los, tiv taus hnav, thiab muaj cov ductility zoo. Tib lub sijhawm, nws muaj cov cua sov zoo thiab hluav taws xob zoo, thiab nws muaj cov qauv zoo thiab kev lag luam yooj yim. Piv nrog hlau thiab txhuas, tooj liab yog qhov tsis tshua muaj, thiab nws cov ntsiab lus nyob hauv lub ntiaj teb' s daim tawv tsuas yog 0.005%, thaum cov ntsiab lus ntawm hlau thiab txhuas ncav 5% thiab 8%, feem. Cov tooj liab dawb yog lub teeb sawv lossis liab liab, tom qab tsim tooj liab oxide zaj duab xis nyob rau saum npoo, qhov zoo li yog tooj liab-xim. Hlau tooj liab, atomic number 29, atomic hnyav 63.54, lub zog nqus tshwj xeeb 8.9 (txhuas 2.7, hlau 7.9, txhuas 11.3, kub 19.3), melting kis 1083 ℃ (txhuas 327, txhuas 660, hlau 1536). Lub ntsiab lus cim Cu yog cov cim luv ntawm nws lub npe Latin cuprum.
Tooj liab muaj ntau lub cev thiab tshuaj zog. Qhov tseem ceeb tshaj plaws yog tias nws cov hluav taws xob kev coj ua yog ntau dua li lwm cov hauv paus hlau thiab hlau, tsuas yog nyiaj tau tshaj nws. Zoo sib xws, nws cov thermal conductivity tseem zoo heev tshaj li lwm cov hlau tshwj tsis yog nyiaj. Feem ntau, tooj liab muaj kev txhim kho corrosion muaj zog, raws li muaj pov thawj los ntawm nws daim ntawv thov hauv architecture thiab duab puab rau txhiab xyoo. Tooj liab raug rau saum huab cua rau lub sijhawm, tom qab oxidation, lub teeb ntsuab tooj liab yuav tsim rau saum npoo. Thaum tsim zaj duab xis, nws yuav tiv thaiv cov kav hlau sab hauv mus tas li. Tooj liab tiv taus cov organic acids thiab alkalis (tshwj tsis yog ammonia), yog li nws tuaj yeem muab faus rau hauv av los yog muab raus rau hauv dej yam tsis muaj xeb.
Ntxiv rau, tooj liab muaj lub zog loj tensile lub zog thiab yog qhov yooj yim rau weld; nws muaj cov yas zoo heev thiab ductility, thiab yog yooj yim rau nrum, yob, nyem, thiab txawm tias tau kos rau hauv cov tooj liab hlau ntau kom ua rau nyias cov tooj liab foils. Tooj liab tuaj yeem ua alloys nrog ntau hlau nrog ntau yam ntxwv thiab siv ntau yam. Nws muaj cov hluav taws xob teb zoo thiab tsis sib nqus. Thaum kawg, nws cov nplua nuj xim, txawm tias nws yog ntshiab tooj lossis tooj hlau, tsim nyog rau cov ntawv thov hauv architecture, kos duab thiab kho kom zoo nkauj.
Tib neeg tau siv tooj liab tau ntau txhiab xyoo. Kev tshawb pom txog keeb kwm ntawm cov qhov ntxa qhia tau tias thaum 6000 xyoo dhau los, cov neeg Iyiv tau siv tooj dag. Tooj liab tsis yog tsuas yog cov hlau qub, tab sis tseem yog cov khoom siv niaj hnub tsim kom muaj zog thiab muaj zog. Tam sim no, tib neeg tib neeg tau nkag mus rau cov kev nplua nuj thiab cov yeeb yuj, haiv neeg muaj ntau haiv neeg uas muaj cov ntaub ntawv hluav taws xob thiab hluav taws xob, uas tau qhib dav dav hauv thaj av rau daim ntawv thov tooj liab. Tooj liab tau siv los ntawm tib neeg ua qauv ntawm ntau hom hlau, alloys thiab sib txuas. Nws tau mob siab rau rau txhua yam ntawm kev tsim khoom thiab lub neej, thiab tau dhau los ua qhov tsis tseem ceeb thiab hlau tseem ceeb rau kev nthuav dav sai sai hauv 21st caug xyoo.
