Raws li cov khoom siv tseem ceeb hauv kev lag luam xws li kev tsim khoom, kev tsim vaj tsev, thiab kev thauj mus los hauv cov kav dej, cov kav hlau steel tuaj yeem faib ua ntau yam sib txawv ntawm cov khoom sib xyaw, cov txheej txheem tsim khoom, thiab cov yam ntxwv ntawm kev ua haujlwm - rau ob pawg loj: siab - lub zog steel kav thiab cov kav hlau zoo tib yam. Txawm hais tias ob qho tib si yuav tshwm sim zoo li sab nrauv, lawv pom qhov sib txawv tseem ceeb ntawm cov khoom siv, cov khoom siv kho tshuab, cov xwm txheej siv tau, thiab kev pabcuam lub neej.
Qhov tseem ceeb ntawm qhov sib txawv ntawm ob yog nyob rau hauv lawv cov khoom sib txawv. Ordinary steel kav feem ntau yog tsim los ntawm cov qauv carbon structural steels (xws li Q195 thiab Q235); Cov ntaub ntawv no muaj cov ntsiab lus tsis tshua muaj carbon thiab muaj cov impurity siab. Yog li ntawd, lawv cov txheej txheem tsim khoom yog ncaj qha- tsis tas yuav tsum muaj kev sib xyaw ua ke sib ntxiv lossis cov txheej txheem kho cua sov zoo tshaj plaws - ua rau cov nqi tsim khoom qis dua. Cov kav dej no muaj peev xwm txaus siab tsuas yog qhov yooj yim thauj khoom-cov kabmob thiab cov kua dej- xa cov kev xav tau, muaj cov khoom siv tshuab tsawg. Hauv qhov sib piv, siab -lub zog steel yeeb nkab yog tsim los ntawm siab- lub zog alloy cov qauv hlau (xws li Q355, Q460, thiab qib siab dua). Cov ntaub ntawv no yog alloyed nrog cov ntsiab lus xws li manganese, chromium, thiab vanadium, thiab tau txais kev kho cua sov tshwj xeeb -xws li quenching thiab tempering, nrog rau normalizing - kom zoo dua steel lub zog, toughness, thiab hnav tsis kam. Tsis tas li ntawd, cov theem impurity yog tswj nruj heev, ua rau cov khoom ntawm purity superior.
Qhov sib txawv tseem ceeb hauv cov khoom siv kho tshuab yog qhov tseem ceeb tshaj qhov sib txawv ntawm ob hom ntawm cov kav hlau steel nyob rau hauv cov nqe lus ntawm daim ntawv thov. Ordinary steel kav muaj qhov tsis tshua muaj tensile thiab yield zog; Feem ntau, lawv lub zog tensile poob ntawm 300 thiab 400 MPa, thaum lawv lub zog tawm los ntawm 200 txog 300 MPa. Tsis tas li ntawd, lawv muaj qhov tsis muaj zog thiab kev cuam tshuam, ua rau lawv muaj kev cuam tshuam rau cov teeb meem xws li deformation lossis tawg thaum raug rau sab nraud quab yuam, kev kub siab, lossis kev thauj khoom nyuaj. Hauv qhov sib piv, siab - lub zog steel yeeb nkab ua kom pom cov khoom zoo heev; lawv lub zog tensile tuaj yeem siab tshaj 400 MPa-nrog rau qee qib txawm tias tshaj 600 MPa- thiab lawv lub zog tawm los ua kom muaj zog tshaj tawm ntawm cov kav hlau zoo tib yam. Tsis tas li ntawd, lawv muaj qhov tshwj xeeb toughness thiab cuam tshuam tsis kam, ua rau lawv tiv taus siab dua, tensile kev nyuaj siab, thiab sab nraud cuam tshuam quab yuam yam tsis yooj yim deforming lossis fracturing. Yog li ntawd, lawv tuav cov qauv kev ruaj ntseg-txawm tias nyob rau hauv cov xwm txheej nyuaj thauj khoom- yog li ua kom muaj kev nyab xeeb ntawm kev ua haujlwm.
Cov xwm txheej sib txawv hu rau cov kev daws teeb meem zoo raws li cov cai tshwj xeeb. Vim lawv cov khoom siv tsis tshua muaj, cov kav hlau steel feem ntau yog siv rau hauv cov chaw yooj yim uas xav tau lub zog tsawg- xws li cov kav dej thiab cov kav dej hauv cov tsev nyob, kev tsim kho ntawm - lub hom phiaj scaffolding, thiab cov kav dej xa mus rau cov khoom me me -. Nyob rau hauv cov xwm txheej no, loads yog lub teeb thiab ib puag ncig tej yam kev mob yog ncaj nraim; Raws li tsis tas yuav tiv thaiv kev kub ntxhov lossis nyuaj sab nraud, kev ua tau zoo ntawm cov kav dej txheem steel yog txaus los ua kom tau raws li qhov tsim nyog xav tau. Hloov pauv, siab -lub zog steel yeeb nkab- txawv los ntawm lawv lub zog zoo dua thiab tawv heev- feem ntau yog siv rau hauv cov ntawv tshwj xeeb uas yuav tsum muaj kev ua tau zoo tshwj xeeb. Cov no suav nrog cov txheej txheem kev txhawb nqa tseem ceeb rau kev tsim kho loj - cov phiaj xwm loj, kev tsim kho choj, siab - cov kav dej siab rau cov roj thiab cov nkev xa tawm, kev tsim cov tshuab hnyav, thiab cov khoom siv rau engineering. Xws li ib puag ncig cuam tshuam nrog hnyav loads thiab complex tej yam kev mob, imposing tsis tshua muaj siab xav tau ntawm lub zog thiab stability ntawm steel kav; yog li ntawd, kev siv cov high{13}}lub zog steel kav yog qhov tseem ceeb los xyuas kom meej ob qho tib si kev nyab xeeb thiab txhim khu kev qha ntawm cov khoom siv.
Distinguished los ntawm lawv txawv specifications thiab manufacturing txheej txheem, ob hom steel yeeb nkab ntaus ib tug sib npaug ntawm practicality thiab durability. Cov kav dej txheem steel muaj qhov tshwj xeeb tshwj xeeb, feem ntau suav nrog cov pa diameters thiab phab ntsa thicknesses; lawv cov khoom siv feem ntau yog nyob ntawm qhov kub dov thiab kos duab txias, tsis tas yuav tsum tau ua haujlwm ntau dua -. Lawv qhov chaw feem ntau khaws cov "dub tawv nqaij" ua tiav lossis tsuas yog tshem tawm yooj yim xeb, ua rau tsis zoo corrosion; Yog li ntawd, lawv muaj feem cuam tshuam rau xeb thiab xeb thaum siv ntev, nrog rau kev pab cuam lub neej ntawm 5 mus rau 10 xyoo. Hauv qhov sib piv, siab - lub zog steel yeeb nkab muaj ntau yam kev qhia tshwj xeeb, tso cai rau kev kho cov kab thiab phab ntsa thicknesses kom tau raws li cov kev xav tau ntawm engineering. Tshaj li kub dov thiab kos duab txias, lawv cov txheej txheem tsim khoom suav nrog cov theem ntxiv -xws li kev kho cua sov thiab tsis yog- kuaj kev puas tsuaj- kom ntseeg tau tias cov khoom ua tau raws li cov qauv nruj. Tsis tas li ntawd, lawv qhov chaw feem ntau raug siv los tiv thaiv- kev kho corrosion (xws li galvanizing lossis kev siv cov txheej tiv thaiv) txhawm rau txhim kho kom ruaj khov, ua rau lub neej ua haujlwm ntawm 15 mus rau 30 xyoo- ntev dua li cov kav hlau txheem.
