Npua hlau thiab hlau yog sib sau ua ke hu ua ferrous hlau.Hlau yog nws cov ntsiab lus tseem ceeb thiab tseem muaj qee yam ntawm cov pa roj carbon thiab lwm yam kab kawm.Alloys nrog cov ntsiab lus carbon tsawg dua 2.11% (ntau) yog hu ua hlau, thiab alloys nrog cov ntsiab lus carbon ntau dua los yog sib npaug li 2.11% (ntau) hu ua npua hlau.
npua hlau tuaj yeem muab faib ua npua hlau rau steelmaking (tseem hu ua hlau dawb) thiab npua hlau rau casting.
Cam khwb cia hlau yog hu ua cam khwb cia hlau.Raws li cov yam ntxwv ntawm graphite, cam khwb cia hlau tuaj yeem muab faib ua pawg hauv qab no: grey cam khwb cia hlau, codenamed HT;cam khwb cia hlau, codenamed QT;corrosion-resistant cam khwb cia hlau;lwm yam cam khwb cia hlau, xws li kub-resistant cam khwb cia hlau thiab malleable cam khwb cia hlau, Malleable cam khwb cia hlau yog code-named KT, kuj hu ua malleable hlau.
cam khwb cia hlau siab cov kav dej thiab fittings tsis yog loj-tsim nyob rau hauv lub tebchaws United States thiab lwm lub teb chaws, tab sis tej zaum yuav loj-tsim nyob rau hauv tej lub teb chaws.Ductile hlau siab kav tau hloov cov kav hlau cam khwb cia.Cov txheej txheem tshwj xeeb suav nrog: ASME B16.3, ASME B16.4, ASME B16.12, ASME B16.42, ASMEB16.42, ASTM A74, ASTM A126, AWWA C110, AWWA C111, AWWA C150, AWWA C153, thiab lwm yam.
Hlau yog qhov tseem ceeb ntawm alloy.Lub ntsiab tivthaiv yog hlau thiab me me ntawm carbon.Nws kuj muaj cov kab mob xws li silicon, manganese, phosphorus, sulfur, chromium, nickel, molybdenum, tungsten thiab vanadium.Kev faib cov hlau yog qhia hauv daim duab
按照化学成分分类
碳素钢
普通碳素钢
优质碳素结构钢
Cov ntsiab lus siab -c≤0.25%
中碳钢—0.25
Cov txiaj ntsig tau zoo -c> 0.6%
同时保证钢的化学成分和力学性能
IB 般S和P的质量分数均不超过
合金钢
合金钢-合金元素总的质量分数一般小于 5%
中合金钢-合金元素总的质量分数一般大于5% 而小于或等于 10%
高合金钢-合金元素总的质量分数一般大于 10%
按照冶炼方法分类
平炉钢
转炉钢
电炉钢
坩炉钢
及
按照炉衬材料分类
按照冶炼脱氧程度分类
酸性钢
碱性钢
沸腾钢-不脱氧的钢
镇静钢-完全脱氧的钢
半镇静钢-半脱氧的钢
按照用途分类
普通钢
优质钢
高级优质钢-钢号后加“高”或“A”
按照赋予其形状的方法分类
铸钢
锻钢
轧压钢
冷拔钢
-- 本文摘自《压力管道设计及工程实例》第二版，主编：宋岢岢
Post lub sij hawm: Sep-07-2021