Qhov ntom ntom yog ib qho ntawm ntau yam khoom ntawm cov hlau.Nws yog xam los ntawm kev faib cov huab hwm coj los ntawm lub ntim.Hlau tuaj nyob rau hauv ntau yam sib txawv.Qhov ceev yog xam los ntawm kev faib cov huab hwm coj los ntawm lub ntim.Qhov ceev ntawm carbon steel yog kwv yees li 7.85 g / cm3 (0.284 lb / in3).

Muaj ntau yam siv rau steel.Stainless hlau, piv txwv li, yog siv rau cov cuab yeej phais thiab cov khoom siv hauv chav ua noj.Nws yog hom hlau uas muaj cov pa roj carbon tsawg thiab tsawg kawg 10.5% ntawm chromium.Qhov no ua rau corrosion kuj.Lwm hom hlau, cov cuab yeej hlau, yog siv rau cov hlau txiav cov cuab yeej laum khoom vim nws nyuaj, tab sis nkig.Tus nqi ntawm cov pa roj carbon steel hauv cov hlau txiav txim siab hardness ntawm cov hlau.Qhov ntau carbon nws muaj, qhov nyuaj steel.Cov pa roj carbon steel feem ntau yog siv rau qhov chaw tsheb.

Hlau thiab nws cov ntawv ntau yam muaj ntau yam siv thoob ntiaj teb.Qhov xwm ntawm cov hlau nyob ntawm nws cov ntsiab lus, uas ua rau muaj qhov sib txawv.Feem ntau, cov hlau, qhov nyuaj nws yog.Qhov kev nyuaj ntawm cov roj carbon, nyob hauv lwm cov steel tsim ntau yam hauv cov nyom lossis cov grainities.(Qhov tshwj xeeb lub ntiajteb txawj nqus los yog qhov sib txheeb ntom ntom yog qhov piv ntawm cov khoom siv qhov ntom ntom rau cov dej.)

Muaj tsib qhov kev faib loj ntawm cov hlau: carbon steel, alloy steel, high-strength low-alloy steel, stainless hlau thiab cov cuab yeej steel.Cov pa roj carbon steel yog qhov ntau tshaj plaws, muaj ntau cov pa roj carbon monoxide, tsim txhua yam los ntawm cov cav tov mus rau cov txaj txaj rau bobby pins.Alloy steels muaj ntau npaum li cas ntawm vanadium, molybdenum, manganese, silicon thiab cooper.Alloy steels tsim cov iav, carving riam thiab txawm tias cov menyuam skates.Stainless hlau muaj chromium, npib tsib xee nrog rau lwm cov hlau alloy uas txhawb nqa lawv cov xim thiab cov tshuaj tiv thaiv xeb.Cov khoom siv stainless hlau muaj xws li cov kav dej, qhov chaw tshuaj ntsiav, cov khoom siv phais mob rau cov khoom siv hauv chav ua noj.Qhov kawg tab sis tsis kawg, cov cuab yeej hlau muaj tungsten, molybdenum ntawm lwm cov hlau alloy.Cov ntsiab lus no tsim lub zog thiab muaj peev xwm ntawm cov cuab yeej steel khoom, uas suav nrog cov khoom siv rau kev tsim khoom thiab cov tshuab.