Taw qhia
Nyob rau hauv lub complex thiab xav tau realm ntawm niaj hnub metallurgy, kev hloov pauv ntawm cov hlau nyoos rau hauv siab -kev ua tau zoo ntawm cov hlau yog qhov kev vam meej ntawm chemistry thiab precision engineering. Thaum daim ntawv qhia tseem ceeb ntawm cov hlau cuam tshuam nrog kev sib txuas ntawm cov hlau nrog cov pa roj carbon monoxide tswj kom zoo, cov txheej txheem tsim khoom tiag tiag yuav tsum muaj ntau yam khoom nruab nrab ntxiv kom ntseeg tau tias cov khoom kawg ua tau raws li cov qauv nruj thiab tshuaj lom neeg. Ntawm cov khoom tseem ceeb no, ferrosilicon sawv tawm los ua ib qho tseem ceeb tshaj plaws master alloys siv nyob rau hauv lub ntiaj teb no ntau lawm chaw niaj hnub no, ua ib tug indispensable tshuaj cuab yeej rau niaj hnub metallurgists thoob ntiaj teb.
Raws li ib tus tswv cuab tseem ceeb thiab tau siv ntau ntawm tsev neeg ferroalloy, ferrosilicon yog qhov tseem ceeb ntawm cov hlau thiab silicon, nrog cov ntsiab lus silicon feem ntau yog li ntawm kaum tsib feem pua mus rau siab tshaj ntawm xya caum - tsib feem pua nyob ntawm cov qib kev lag luam thiab cov ntawv thov tshwj xeeb. Thaum cov khoom tshwj xeeb no ua haujlwm rau ntau yam kev ua haujlwm -xws li los ntawm kev ua haujlwm inoculants nyob rau hauv grey thiab ductile cam khwb cia hlau ntau lawm los ua cov ntaub ntawv tseem ceeb rau cov tshuaj synthesis ntawm lwm yam engineering alloys siab heev -lawv lub luag hauj lwm tseem ceeb tshaj plaws thiab thoob plaws hauv lub ntiaj teb steelmaking yog deoxidation.
Unrefined molten steel tawm hauv thawj lub qhov cub melting yog hnyav heev nrog cov roj yaj, tshwj xeeb tshaj yog cov pa oxygen, uas tuaj yeem cuam tshuam qhov kev ncaj ncees, ductility, cuam tshuam, thiab tag nrho cov khoom zoo ntawm cov hlau yog tias tsis kho. Taw qhia ferrosilicon rau hauv lub molten da dej muab ib qho kev txhim khu kev qha, muaj txiaj ntsig zoo rau kev tshem tawm cov pa oxygen tsis xav tau sai. Tshawb nrhiav cov cuab yeej zoo sib xws, hauv qab chemistry, cov txheej txheem tsim khoom, thiab cov txiaj ntsig kev ua haujlwm ntawm ferrosilicon qhia tias vim li cas nws tseem yog lub hauv paus tseem ceeb ntawm kev ua lag luam niaj hnub thiab kev tshawb fawb metallurgical.
Qhov teeb meem ntawm Oxygen hauv Liquid Steel
Yuav kom nkag siab tias yog vim li cas ferrosilicon yog qhov tseem ceeb tshaj plaws hauv kev siv hlau niaj hnub no, ib tus yuav tsum xub tshuaj xyuas cov teeb meem tshuaj lom neeg thiab cov thermodynamic qhov tseeb ntawm kev lag luam steelmaking. Thaum lub sij hawm pib melting thiab refining theem-txawm yog raug tua nyob rau hauv ib tug yooj yim oxygen rauv los yog ib tug advanced hluav taws xob arc rauv- raw cov ntaub ntawv, seem hlau, thiab txhaj cov pa oxygen sib cuam tshuam nyob rau hauv huab ua hauj lwm kub siab tshaj kaum rau puas degrees Celsius. Thaum cov pa yog nruj me ntsis tsim nyog nyob rau theem no kom hlawv cov pa roj carbon ntau dhau thiab oxidize lwm yam tsis zoo xws li phosphorus, sulfur, thiab silicon los ntawm cov hlau kub, nws tawm hauv qab cov tshuaj lom neeg tseem ceeb: qhov siab ntawm cov pa oxygen tseem nyob hauv cov kua hlau matrix.
Yog tias cov kua hlau uas muaj cov pa oxygen ntau ntau tau tso cai rau txias, cam khwb cia, thiab khov kho yam tsis muaj kev cuam tshuam tshuaj lom neeg, kev cuam tshuam loj ntawm metallurgical yuav tshwm sim. Raws li molten kub poob thaum lub sij hawm casting, solubility ntawm gases nyob rau hauv cov kua hlau txo sharply. Cov residual yaj oxygen reacts nrog cov pa roj carbon monoxide seem los tsim cov pa roj carbon monoxide npuas. Qhov tshwm sim no, hu ua effervescence lossis boiling, tsim cov porosity sab hauv, blowholes, nto fissures, thiab txaus ntshai gas hnab ris nyob rau hauv lub solidified steel casting.
Tsis tas li ntawd, cov pa oxygen residual reacts aggressively nrog hlau thiab lwm yam hlau cov ntsiab lus los ua non{0}}metallic oxide inclusions. Cov microscopic inclusions ua raws li kev ntxhov siab loj hauv cov crystalline steel matrix, txo cov khoom siv lub zog tensile, cuam tshuam toughness, qaug zog, thiab tag nrho cov ductility. Hauv kev siv cov txheej txheem tseem ceeb-xws li siab- cov kav xa dej siab, hnyav- lub nkoj ua haujlwm siab, xav tau cov khoom siv tsheb, thiab loj - nplai architectural infrastructure- xws li kev tsis muaj zog sab hauv tuaj yeem ua rau muaj kev puas tsuaj loj hauv kev thauj khoom. Yog li ntawd, tshem tawm lossis ua kom tsis muaj pa oxygen yog qhov tsim nyog ua ntej ua lag luam - qib steel, thiab cov txheej txheem purification tseem ceeb no vam khom rau cov tshuaj tshwj xeeb deoxidizers xws li ferrosilicon.
Tshuaj Mechanisms ntawm Silicon Deoxidation
Deoxidation yog ib qho kev sib tw tshuaj lom neeg rau oxygen affinity ntawm qhov kub siab. Hlau muaj qhov sib txawv me ntsis rau cov pa oxygen, tab sis lwm cov ntsiab lus tshwj xeeb muaj qhov cuam tshuam zoo dua rau cov pa oxygen atoms. Thaum xws li ib lub ntsiab yog nkag mus rau hauv lub turbulent molten steel da dej, nws aggressively strips oxygen deb ntawm hlau atoms, tsim ruaj khov khoom los yog kua oxide tebchaw uas muaj peev xwm ces yuav xyuam xim sib cais los ntawm cov kua hlau los ntawm flotation thiab slag absorption.
Silicon muaj cov tshuaj lom neeg muaj txiaj ntsig zoo heev rau cov pa oxygen, ua rau nws muaj txiaj ntsig zoo purifying tus neeg sawv cev. Thaum ferrosilicon meticulously ntxiv rau cov kua hlau, nws dissolves sai thiab uniformly rau hauv cov hlau molten. Thaum tag nrho yaj, cov silicon atoms hnov mob tam sim nrog cov pa oxygen uas muaj nyob hauv cov hlau yaj. Thawj cov tshuaj tiv thaiv ua rau muaj kev tsim ntawm silicon dioxide, feem ntau hu ua silica:
Si(solved)+2O(dissolved) →SiO2(solid/liquid)
Cov tshuaj tiv thaiv tshuaj no yog exothermic heev, txhais tau tias nws tso tawm ntau lub zog thermal thaum lub sijhawm kho. Qhov kev tso cua sov no yog qhov muaj txiaj ntsig zoo vim tias nws pab tswj qhov kub ntawm lub molten da dej thaum lub sij hawm ladle metallurgy kev kho mob, tiv thaiv ntxov ntxov khov ntawm cov hlau. Cov silica molecules uas tau tsim tshiab tsis nyob twj ywm tsis tu ncua hauv cov hlau tsis tas li. Vim tias lawv muaj qhov ntom ntom dua li cov kua hlau nyob ib puag ncig thiab zoo li agglomerate rau hauv cov khoom loj dua, cov khoom siv silica no nce tsis tu ncua mus rau ntawm lub ladle. Nyob ntawd, lawv tau nqus mus rau hauv cov txheej txheem tiv thaiv ntawm cov hluavtaws slag ntab saum cov hlau molten, zoo txhuam cov hlau huv ntawm oxygen impurities.
Nyob rau hauv kev sib piv rau lwm yam nrov deoxidizing neeg ua hauj lwm xws li ntshiab txhuas los yog manganese, silicon muaj txawv thermodynamic thiab kinetic zoo. Thaum txhuas yog ib qho deoxidizer uas muaj zog heev uas muaj peev xwm ua tiav cov pa oxygen tsawg heev, qee zaum nws tuaj yeem tsim nyuaj, abrasive aluminium oxide suav nrog uas ua rau nyuaj rau kev ua haujlwm tom ntej thiab dov txheej txheem. Silicon, nquag siv ua ke nrog manganese, muab ib qho kev sib npaug deoxidation mus kom ze uas ua kom zoo tag nrho cov hlau huv thaum tswj xyuas cov kua dej zoo heev thiab castability.
Kev tsim khoom thiab qib ntawm Ferrosilicon
Cov txiaj ntsig zoo kawg nkaus ntawm ferrosilicon ua tus thawj deoxidizer yog qhov tob tob hauv kev tsim cov khoom nws tus kheej li cas. Kev tsim cov ferroalloy tseem ceeb no yuav tsum muaj cov txheej txheem kev lag luam hnyav nyob ib puag ncig loj - nplai submerged electric arc rauv ua haujlwm raws li kev tswj xyuas nruj thiab tshuaj lom neeg. Cov ntaub ntawv tseem ceeb muaj xws li high-purity quartz lossis silica pob zeb ua lub hauv paus ntawm silicon, ua ke nrog qib siab - qib carbonaceous txo cov neeg ua haujlwm xws li metallurgical coke, thee, charcoal, thiab wood chips, nrog rau cov hlau seem los yog nplai los muab cov khoom siv hlau tsim nyog.
Nyob rau hauv lub tshuab hluav taws xob ua lag luam, cov pa roj carbon loj lossis graphite electrodes dhau cov hluav taws xob hnyav dhau los ntawm tus nqi, ua kom muaj zog thermal zog uas nce mus txog ob txhiab degrees Celsius. Nyob rau hauv cov huab cua kub no, cov carbonaceous txo cov neeg ua haujlwm tshem tawm cov pa atoms deb ntawm silica xuab zeb nyob rau hauv ib tug nruam carbothermic txo cov tshuaj tiv thaiv, tawm hauv qab ib tug molten hlau- silicon alloy pooled nyob rau hauv qab ntawm lub cub tawg. Cov kua alloy yog ib ntus tapping, cam khwb cia rau hauv qhov txias txias, crushed, thiab tom qab ntawd soj ntsuam mus rau hauv cov khoom lag luam meej qhov ntau thiab tsawg raws li cov kev cai steel zeb.
Ferrosilicon yog kev lag luam muab faib ua cov qauv sib txawv raws li qhov feem pua ntawm nws qhov hnyav silicon. Cov qib txheem feem ntau suav nrog FeSi75 (muaj kwv yees li xya caum- tsib feem pua silicon), FeSi65, thiab FeSi45, nrog rau cov qib qis dua - feem pua. Txhua qib muaj qhov sib txawv ntawm lub cev thiab tshuaj lom neeg tsim nyog rau ntau theem ntawm kev tsim steel:
Siab -Silicon Qib (xws li FeSi75):Cov no feem ntau xaiv thaum lub siab tshaj plaws silicon rov qab thiab muaj zog deoxidation yuav tsum tau nrog tsawg kawg nkaus ntxiv, ua rau lawv zoo tagnrho rau tshwj xeeb alloy steels, hluav taws xob daim ntawv hlau, thiab foundry inoculant daim ntaub ntawv.
Txuj thiab qis-Silicon Qib (piv txwv li, FeSi45):Cov no feem ntau yog siv nyob rau hauv cov pa roj carbon steel ntau lawm thiab hnyav foundry ua hauj lwm qhov twg balanced deoxidation thiab tswj kev hloov alloy yog xav tau yam tsis muaj tshaj - faib siab - nqi silicon units.
Kev ua tib zoo xaiv qib tso cai rau metallurgists kom zoo- kho cov tshuaj muaj pes tsawg leeg ntawm cov yaj nrog qhov zoo tshaj plaws precision, kom ntseeg tau tias cov khoom hlau kawg ua tiav cov khoom siv kho qhov tseeb xav tau los ntawm kev lag luam kawg - cov neeg siv.
Kev ua haujlwm zoo thiab kev sib koom ua ke hauv Niaj hnub Steelmills
Nyob rau hauv lub nrawm -paced thiab nqi- ib puag ncig nco qab ntawm cov nroj tsuag niaj hnub steel, kev ua haujlwm tau zoo thiab kev muaj peev xwm ntawm kev lag luam tsuas yog ib qho tseem ceeb xws li tshuaj lom neeg precision. Ferrosilicon muab ntau qhov sib txawv ntawm kev ua haujlwm zoo uas ua rau nws cov xwm txheej ua ib qho cuab yeej tseem ceeb rau cov tuam txhab steel thoob ntiaj teb.
Ua ntej, ferrosilicon dissolves rau hauv cov kua hlau nrog tshwj xeeb yooj yim thiab ceev. Vim tias nws cov ntsiab lus melting yog qis dua li ntawm cov ntshiab silicon, nws sib koom ua ke zoo rau hauv cov da dej molten yam tsis tas yuav tsum muaj kev sib xyaw ua ke ntau dhau los yog cov cua kub mus ntev. Qhov kev tshem tawm sai sai no txo qis lub sijhawm kho hauv lub ladle rauv, txhawb nqa tag nrho cov khoom siv thiab txo cov hluav taws xob siv hluav taws xob ib tuj ntawm cov hlau ua tiav.
Thib ob, ferrosilicon tsis tshua ua haujlwm hauv kev sib cais; Nws ua lub luag haujlwm tseem ceeb hauv kev sib koom ua ke nrog rau lwm cov khoom siv hlau, tshwj xeeb tshaj yog manganese thiab carbon. Steelmakers nquag siv cov khoom sib xyaw deoxidizers lossis cov tswv yim sib txuas ntxiv -xws li kev sib xyaw ferromanganese, silicomanganese, thiab ferrosilicon- kom ua tau zoo deoxidation kinetics. Thaum silicon thiab manganese nyob ib txhij nyob rau hauv lub yaj, lawv tsim complex silicate inclusions uas coalesce thiab ntab tawm ntawm cov hlau sai npaum li cas sai dua li ntshiab silica los yog manganese oxide hais ib leeg. Qhov kev sib koom tes tu kev ua haujlwm no ua kom muaj kev huv huv zoo kawg nkaus steel matrix tsis muaj teeb meem cuam tshuam.
Tsis tas li ntawd, dhau ntawm nws lub luag haujlwm tseem ceeb ua tus deoxidizer, silicon tau qhia los ntawm ferrosilicon ua cov khoom muaj txiaj ntsig zoo - kev daws teeb meem hauv cov khoom tiav steel. Silicon dissolves ncaj qha mus rau hauv lub ferrite siv lead ua matrix, ua rau nws hardness thiab tensile zog yam tsis muaj kev txi loj heev ductility los yog toughness. Hauv cov ntawv thov tshwj xeeb, xws li kev tsim cov ntawv hluav taws xob siv hluav taws xob siv hluav taws xob hloov hluav taws xob thiab cov tshuab hluav taws xob, kev tswj cov silicon ntxiv yog txhob txwm khaws cia los txhim kho cov hlau nplaum permeability thiab txo cov tub ntxhais hluav taws xob poob. Qhov no dual functionality- ua raws li ib tug ua purifier thaum lub sij hawm tsim thiab ib tug kev ua tau zoo enhancer nyob rau hauv cov khoom kawg - qhia tau hais tias tus tshwj xeeb muaj nqi ntawm no ntau yam khoom.
Xaus
Hauv cov ntsiab lus, txoj kev taug kev los ntawm cov hlau tsis huv mus rau siab - lub zog, flawless structural steel yog fraught nrog cov teeb meem tshuaj, qhov tseem ceeb ntawm lawv yog kev tshem tawm ntawm detrimental oxygen impurities. Los ntawm nws qhov tshwj xeeb tshuaj affinity rau oxygen, siab thermal stability, thiab sai dissolution kinetics, ferrosilicon proves nws tus kheej lub sij hawm thiab dua li ib qho tseem ceeb deoxidizer nyob rau hauv niaj hnub steelmaking.
Raws li cov khoom siv pob zeb ntawm kev lag luam ferroalloy dav, ferrosilicon ua ntau tshaj li qhov yooj yim ntxuav cov hlau molten ntawm cov roj yaj; nws enables metallurgists los tswj inclusion tsim, optimize hluav taws xob arc thiab ladle rauv efficiency, thiab muab cov khoom muaj txiaj ntsig zoo rau cov khoom siv hlau kawg. Txawm hais tias kev txhawb nqa kev tsim kho ntawm cov skyscrapers, complex automotive architectures, los yog cov kav dej tseem ceeb, ferrosilicon ua haujlwm raws li qhov chaw nyob ntsiag to tseem ceeb heev tom qab lub cev pob txha ntawm niaj hnub ntiaj teb kev vam meej.
