Yuav Ua Li Cas Thiaj Ua Tau Cov Hlau Alloy Rau Cov Cheebtsam Tshuab
Cov hlau sib xyaw yog cov khoom siv dav tshaj plaws hauv kev tsim cov khoom siv tshuab vim tias lawv sib xyaw cov khoom zoo tshaj plaws uas tsis pom muaj nyob rau hauv cov hlau ntshiab. Los ntawm kev sib xyaw ob lossis ntau yam khoom - piv txwv li, hlau nrog carbon, chromium, nickel, molybdenum, lossis vanadium - peb tuaj yeem ua tiav lub zog tensile, hnav tsis kam, corrosion tsis kam, toughness, thiab txawm tias ruaj khov ntawm qhov kub siab. Hauv kev lag luam tshuab, qhov zoo ntawm cov hlau sib xyaw txiav txim siab lub neej ua haujlwm ntawm cov khoom xws li shafts, iav, bearings, springs, txiv ntoo thiab bolts, cav blocks, thiab ntau yam khoom uas ua haujlwm nyob rau hauv dynamic loads. Yog li ntawd, cov txheej txheem ntawm kev ua cov hlau sib xyaw yuav tsum tau ua nyob rau hauv kev tswj hwm nruj, los ntawm kev xaiv cov khoom siv mus rau kev sim zaum kawg.
1. Txheeb xyuas qhov yuav tsum tau ua ntawm cov khoom siv hauv tshuab
Ua ntej tsim cov hlau sib xyaw ua ke, thawj kauj ruam yog nkag siab txog kev ua haujlwm ntawm lub tshuab uas yuav tsum tau tsim. Txhua qhov khoom muaj cov khoom siv sib txawv. Cov iav xav tau qhov nyuaj ntawm qhov chaw thiab lub hauv paus ductile kom tiv taus kev poob siab. Cov ncej xav tau qhov tawv thiab kev qaug zog. Cov khoom hauv cov chaw ua haujlwm corrosive, xws li cov twj tso kua mis tshuaj lossis cov cav marine, xav tau kev tiv thaiv corrosion zoo. Raws li cov kev cai no, cov kws ua haujlwm khoom siv txiav txim siab cov khoom siv lub hom phiaj: lub zog tensile (UTS), lub zog tso zis, qhov nyuaj, kev cuam tshuam toughness, ductility, hnav tsis kam, thiab corrosion lossis kub siab tiv taus.
Thaum cov khoom siv tau teeb tsa tiav lawm, hom hlau sib xyaw uas tsim nyog yuav raug xaiv, xws li hlau carbon, hlau sib xyaw tsawg, hlau tsis xeb, hlau cam khwb cia, hlau txhuas, lossis hlau tooj liab. Qhov kev xaiv no kuj suav nrog cov nqi tsim khoom, kev muaj khoom siv raw, kev ua haujlwm tau yooj yim, thiab cov qauv kev lag luam siv tau.
2. Xaiv cov khoom sib xyaw ua ke
Cov khoom sib xyaw ua ke yog "daim ntawv qhia" tseem ceeb uas txiav txim siab qhov microstructure thiab cov khoom siv kho tshuab ntawm cov khoom siv. Piv txwv li feem ntau yog hlau, ib qho sib xyaw ua ke ntawm hlau (Fe) thiab carbon (C). Carbon ua rau muaj kev tawv thiab lub zog, tab sis ntau dhau tuaj yeem txo qhov ductility. Kev ntxiv chromium (Cr) tuaj yeem txhim kho kev xeb thiab kev tawv, thaum nickel (Ni) txhim kho kev tawv thiab kev tiv thaiv kev tawg. Molybdenum (Mo) txhim kho kev tiv thaiv kub siab thiab ua rau muaj zog, thaum vanadium (V) txhim kho qhov loj ntawm cov noob thiab txhim kho kev tiv thaiv kev hnav.
Hauv kev lag luam, cov khoom sib xyaw ua ke feem ntau ua raws li cov qauv xws li ASTM, JIS, DIN, lossis SNI kom ntseeg tau tias zoo sib xws. Piv txwv li, cov iav feem ntau siv cov hlau sib xyaw xws li SCM (Cr-Mo), uas tsim nyog rau kev kho cua sov. Rau cov chaw muaj xeb, cov hlau tsis xeb xws li hom 304 lossis 316 (muaj Cr thiab Ni, thiab hauv 316, Mo ntxiv).
3. Npaj cov khoom siv raw thiab kev tswj xyuas zoo thawj zaug
Cov khoom siv raw rau kev sib xyaw ua ke tuaj yeem suav nrog cov hlau ntshiab, ferroalloys (piv txwv li, ferrochrome, ferromanganese), thiab cov khoom seem uas tau txheeb xyuas. Cov khoom seem siv dav rau nws qhov kev siv nyiaj tsim nyog, tab sis nws yuav tsum tau tswj hwm nruj me ntsis vim tias nws tuaj yeem muaj cov khoom tsis huv xws li sulfur (S), phosphorus (P), lossis lwm yam khoom tsis xav tau. Cov ntsiab lus sulfur thiab phosphorus ntau tuaj yeem ua rau cov khoom siv ua brittle, dhau los ntawm kev kub cracking, thiab txo qhov kev tiv thaiv qaug zog.
Ua ntej yaj, kev tshuaj xyuas cov khoom siv raw yuav ua tiav: kev cais raws hom, tshem tawm cov roj / xeb ntau dhau, thiab kev sim cov khoom siv siv cov txheej txheem xws li Optical Emission Spectroscopy (OES). Qhov kev tswj hwm no yog qhov tseem ceeb los txiav txim siab qhov sib xyaw ua ke kawg.
4. Cov txheej txheem yaj thiab kev ua hlau
Cov theem tseem ceeb hauv kev ua cov hlau sib xyaw yog yaj thiab sib tov cov khoom hauv lub cub tawg. Cov hom cub tawg feem ntau muaj xws li:
1. Lub Cub Hluav Taws Xob Induction: Haum rau cov hlau sib xyaw nrog kev tswj cov khoom sib xyaw kom raug thiab kev huv huv ntawm cov hlau. Siv dav rau cov hlau sib xyaw thiab cov hlau sib xyaw uas tsis yog hlau.
2. Lub Rauv Hluav Taws Xob Hluav Taws Xob (EAF): Feem ntau siv rau hauv cov lag luam hlau loj, uas muaj peev xwm yaj cov khib nyiab ntau heev.
3. Lub Tshuab Rauv Thiab Lub Tshuab Hloov Pauv (BOF): Feem ntau yog siv rau kev tsim cov hlau thiab hlau loj, tshwj xeeb yog los ntawm cov hlau.
Thaum yaj, cov khoom siv raug qhia ua ntu zus. Thaum cov hlau yaj mus txog, cov khoom sib xyaw raug ntxiv raws li kev xam. Yuav tsum ceev faj ntxiv: qee cov ntsiab lus tsis ruaj khov lossis cuam tshuam nrog oxygen, yog li qhov kev txiav txim thiab lub sijhawm ntawm kev ntxiv cuam tshuam rau cov txiaj ntsig. Piv txwv li, Manganese (Mn), feem ntau yog ntxiv los pab "khi" sulfur, thaum txhuas (Al) feem ntau yog siv rau deoxidation (txo cov pa oxygen yaj) kom tiv thaiv kev tsim cov porosity thiab cov khoom tsis zoo.
5. Kev ua kom cov hlau ua kua: deoxidation, desulfurization, thiab degassing
Rau cov khoom siv cav kom muaj zog thiab txhim khu kev qha, cov hlau uas yaj yuav tsum "huv." Cov khoom tsis huv xws li oxygen, hydrogen, nitrogen, sulfur, thiab cov khoom tsis yog hlau tuaj yeem ua rau muaj kev tawg thiab txo qhov kev tiv taus qaug zog.
Qee txoj kev ntxuav muaj xws li:
- Deoxidation: Ntxiv Al, Si, lossis Mn los khi cov pa oxygen.
– Desulfurization: Txo cov sulfur los ntawm kev ntxiv cov txiv qaub ntsuab (CaO) thiab tsim cov slag uas muaj peev xwm nyiam cov sulfur.
– Kev siv lub tshuab nqus tsev los tshem cov pa roj uas yaj (tshwj xeeb yog hydrogen thiab nitrogen) los ntawm kev siv lub tshuab nqus tsev, qhov no tseem ceeb heev rau cov hlau zoo rau cov khoom tseem ceeb xws li cov turbine shafts lossis cov iav high voltage.
– Kev ua kom cov slag huv: Cov slag ua lub luag haujlwm hauv kev ntes cov khoom tsis huv. Kev tswj cov khoom sib xyaw ntawm cov slag (lime, fluorspar, alumina) txiav txim siab qhov ua tau zoo ntawm kev ua kom huv.
6. Kev nchuav thiab kev tsim thawj zaug (casting)
Thaum cov hlau uas yaj lawm muaj pes tsawg leeg thiab huv si raws li cov hom phiaj, theem tom ntej yog casting. Muaj ob txoj hauv kev tseem ceeb:
1. Kev siv cov hlau ingot casting: Cov hlau uas yaj lawm raug nchuav rau hauv ib lub pwm loj, tom qab ntawd cov hlau ingot raug ua tiav ntxiv los ntawm kev forging lossis dov. Txoj kev no yog ib txwm muaj rau cov khoom uas xav tau cov qauv ntom ntom thiab cov khoom siv kho tshuab siab.
2. Kev casting tas mus li: Cov hlau uas yaj lawm raug nchuav tas mus li rau hauv cov billets, blooms, lossis slabs. Txoj kev no ua tau zoo rau kev tsim khoom ntau thiab zoo tas mus li.
Kev tswj qhov kub thiab txias yog qhov tseem ceeb heev rau kev nchuav. Qhov kub thiab txias siab dhau tuaj yeem ua rau muaj kev oxidation ntau ntxiv; qhov kub thiab txias qis dhau tuaj yeem ua rau muaj kev khiav tsis raug (cov hlau tsis puv pwm tag nrho). Tsis tas li ntawd, kev tsim ntawm txoj kab nchuav thiab lub qhov nce cuam tshuam rau qhov shrinkage porosity thiab kev sib cais ntawm cov khoom.
7. Cov txheej txheem tsim: forging, dov, thiab pib machining
Ntau yam khoom siv hauv tshuab yog tsim los ntawm cov txheej txheem yas los txhim kho cov qauv ntawm cov khoom. Piv txwv li, kev forging tuaj yeem ua rau muaj zog thiab tawv dua los ntawm kev ua kom cov noob nplej zoo thiab coj cov noob nplej kom ua raws li cov duab ntawm cov khoom. Kev dov feem ntau yog siv los ua cov pas nrig, phaj, lossis cov duab profile.
Tom qab ua tiav lawm, feem ntau cov khoom yuav raug siv tshuab thawj zaug (ua kom ntxhib) kom tau txais cov duab ze rau qhov loj kawg, tseg ib qho kev tso cai rau kev kho cua sov thiab cov txheej txheem tiav.
8. Kev kho cua sov kom ua tiav cov khoom xav tau
Cov hlau sib xyaw rau cov khoom siv tshuab yuav luag ib txwm xav tau kev kho cua sov kom ua tiav cov khoom zoo tshaj plaws. Qee qhov kev kho cua sov feem ntau suav nrog:
- Annealing: Ua kom cov khoom mos, txo cov kev ntxhov siab seem, txhim kho kev ductility.
- Normalizing: Normalizes lub microstructure, txhim kho uniformity thiab lub zog piv rau annealing.
- Kev ua kom txias thiab ua kom sov: Kev ua kom txias (ua kom txias sai) ua rau lub zog tawv dua, tom qab ntawd kev ua kom sov txo qhov brittleness thiab sib npaug lub zog nrog kev tawv.
– Carburizing / nitriding: Kev kho kom tawv ntawm qhov chaw rau cov iav thiab cov khoom sib txhuam. Carburizing ntxiv cov pa roj carbon rau ntawm qhov chaw; nitriding ntxiv nitrogen los tsim ib txheej tawv, tiv taus hnav.
Qhov kev xaiv ntawm cov kev ntsuas - kub, lub sijhawm tuav, thiab cov khoom siv txias (dej, roj, polymer, roj) - muaj feem cuam tshuam loj rau qhov nyuaj kawg, kev cuam tshuam, thiab kev pheej hmoo ntawm kev tawg.
9. Kev ua tiav, kev tshuaj xyuas thiab kev sim
Kauj ruam kawg yog kev ua kom tiav thiab kev tswj xyuas zoo. Kev ua kom tiav tuaj yeem suav nrog kev siv tshuab kom raug, kev sib tsoo, kev txhuam, thiab kev txheej, yog tias tsim nyog. Tom qab ntawd, kev sim raug ua kom ntseeg tau tias cov khoom siv ua tau raws li cov lus qhia:
- Kev sim tshuaj lom neeg (OES lossis XRF).
- Kev sim qhov nyuaj (Rockwell, Brinell, Vickers).
- Kev ntsuam xyuas tensile thiab impact (Charpy)
- Kev ntsuam xyuas metallographic kom pom cov microstructure, qhov loj ntawm cov noob, thiab cov khoom suav nrog.
- NDT (Kev Ntsuas Tsis Ua Rau Puas Tsuaj) xws li kev kuaj ultrasonic, cov khoom sib nqus, cov xim nkag mus rau hauv kom pom cov qhov tsis zoo yam tsis muaj kev puas tsuaj rau cov khoom.
- Kev sim qaug zog rau cov khoom uas raug rau cov khoom thauj cyclic.
Yog tias pom muaj qhov tsis sib xws, yuav muaj kev kho kom raug: kev hloov kho cov khoom sib xyaw, kev kho cua sov kom zoo dua, lossis kev txhim kho cov txheej txheem nchuav thiab tsim.
Xaus
Kev tsim cov hlau sib xyaw rau cov khoom siv hauv tshuab yog ib qho txheej txheem sib txuas ua ke: los ntawm kev txiav txim siab cov khoom siv uas xav tau, xaiv cov khoom sib xyaw, yaj thiab ua kom zoo, casting, tsim, kho cua sov, thiab sim zaum kawg. Tus yuam sij rau kev vam meej yog kev tswj hwm cov khoom sib xyaw thiab kev huv ntawm cov hlau, nrog rau kev tswj hwm cov txheej txheem kom meej kom ntseeg tau tias cov qauv me me ua tau raws li qhov xav tau ntawm cov khoom. Nrog rau cov txheej txheem kev qhuab qhia thiab cov qauv, cov hlau sib xyaw tuaj yeem tsim cov khoom siv hauv tshuab uas muaj zog, ruaj khov, thiab muaj kev nyab xeeb rau kev siv hauv ntau yam kev siv hauv kev lag luam.
Yog tias koj xav tau, kuv tuaj yeem kho tsab xov xwm no kom meej dua - piv txwv li, tsom mus rau cov hlau sib xyaw ua ke, cov hlau sib xyaw ua ke hauv tsheb, lossis cov hlau tsis xeb ntawm lub twj tso kua mis - ua tiav nrog cov piv txwv sib xyaw thiab cov duab qhia txog cov txheej txheem.
