Qhov zoo ntawm cov khoom siv tooj liab

Cov kav dej tooj liab muaj ib qho kev ntxhib los mos, tsis yooj yim corroded, thiab tiv taus qhov kub thiab txias, ua rau lawv tsim nyog siv rau ntau qhov chaw. Piv nrog rau qhov no, qhov tsis zoo ntawm ntau lwm cov kav dej yog qhov pom tseeb, xws li cov kav dej galvanized steel feem ntau siv nyob rau hauv cov tsev nyob yav dhau los, uas yog feem ntau ua rau corrosion. Yog tias siv rau lub sijhawm luv luv, cov teeb meem xws li yellowing ntawm kais dej thiab txo cov dej ntws yuav tshwm sim. Qee cov ntaub ntawv kuj muaj qhov txo qis hauv lub zog ntawm qhov kub thiab txias, uas tuaj yeem ua rau muaj kev nyab xeeb thaum siv hauv cov kav dej kub. Tooj liab muaj qhov melting point txog 1083 degrees Celsius, thiab qhov kub ntawm cov dej kub yog qhov 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 4500 xyoo hauv cov pyramids ntawm Egypt, uas tseem siv niaj hnub no.