Annealing ntawm hlau ua ib hom kev kho cua kub. Technology ntawm co

Tsim cov ntaub ntawv tshiab thiab kev tswj lawv cov khoom yog kos duab ntawm cov tshuab hlau. Ib qho ntawm nws cov cuab yeej yog kev kho tshav kub. Cov txheej txheem tso cai rau koj hloov cov yam ntxwv thiab raws li, qhov muaj peev xwm ntawm kev siv cov alloys. Kev tshem tawm cov hlau yog qhov kev xaiv ntau tshaj qhov kev tshem tawm cov kev ua txhaum ntawm cov khoom, ua rau lawv lub zog thiab kev cia siab.

Cov hauj lwm ntawm tus txheej txheem thiab nws cov kab txawv

Txoj kev ua haujlwm raug ua kom tiav nyob rau hauv thiaj li:

• Optimization ntawm cov txheej txheem intracrystalline, cov ordering ntawm cov ntsiab lus alloying;
• Tsawg ntxig rau sab nrauv thiab kev nyuab siab vim kev hloov kev kub ntxhov ceev;
• Ua kom ua raws li cov khoom rau tom qab ua haujlwm.

Kev ua haujlwm classical yog hu ua "kev ua kom tiav," txawm li cas los xij, muaj ntau yam ntawm nws cov khoom, nyob ntawm cov khoom siv thiab cov haujlwm ntawm cov dej num: tsis tiav, qis, diffusion (homogenization), isothermal, recrystallization, normalization. Tag nrho cov uas zoo sib xws nyob rau hauv tus, tab sis lub hom ntawm steel tshav kub kev kho mob no ho sib txawv.

Thermal ua raws li daim duab

Tag nrho cov kev hloov hauv hlau thiab steel kev lag luam, uas yog raws li qhov kev ua si ntawm kub, kom meej meej sib haum rau daim duab ntawm hlau-carbon alloys. Nws yog ib qho kev pab kom pom cov microstructure ntawm carbon steel los yog cast iron, thiab cov ntsiab lus ntawm kev hloov ntawm cov qauv thiab lawv cov nta hauv cov cua kub lossis txias.

Cov cuab yeej ntawm cov hlau yog tswj txhua yam kev tsis zoo ntawm carbon hlau los ntawm lub sijhawm no. Rau tsis tiav, tsis tshua muaj thiab recrystallization "pib" kab kub qhov tseem ceeb yog PSK, namely nws tseem ceeb heev taw tes _Ac1. Tag nrho cov annealing thiab normalizing steel thermal oriented GSE kab daim duab, nws tseem ceeb heev taw tes thiab lub Ac ₃ Ac _m. Tsis tas li ntawd, daim duab qhia meej meej tias qhov kev sib raug zoo ntawm ib hom kev kho cua sov twg nrog rau hom khoom siv nrog rau cov ntsiab lus ntawm cov ntsiab lus thiab cov ntsiab lus ntawm kev sib raug zoo ntawm kev coj ua rau kev txheeb ze.

Tag nrho kev sib ntxub

Khoom: castings thiab forgings los ntawm pre-eutectoid alloy, thaum cov muaj pes tsawg leeg ntawm cov hlau yuav tsum sau cov pa hauv qhov nyiaj mus txog 0.8%.

Hom phiaj:

• Qhov hloov siab tshaj plaws nyob rau hauv lub microstructure tau txais los ntawm casting thiab kub siab, nqa cov heterogeneous coarse-grained ferritic-pearlitic composition mus rau hauv ib lub qauv uniform nplua-tsim;
• Txo hauv kev ua kom nruj thiab ua raws li kev ua haujlwm tom qab.

Tshuab. Annealing steel ntawm kub saum toj no tseem ceeb heev taw tes 30-50˚S _AC3. Thaum cov hlau nce mus txog cov thermal cov yam ntxwv, lawv tswj tau nyob rau theem no rau qee lub sijhawm, cia tag nrho cov kev hloov tsim nyog yuav tsum tau ua kom tiav. Loj pearlitic thiab ferritic nplej tag kis mus rau hauv austenite. Cov kauj ruam tom ntej yog qis cua txias nrog rau lub tshuab ua kom sov, thaum lub sijhawm ferrite thiab perlite, uas muaj nplua nplej thiab homogeneous qauv, yog rov cais los ntawm cov austenite.

Qhov ua tiav ntawm cov hlau tso cai rau tshem tawm cov feem ntau txoj hauv kev tsis xws luag, tab sis nws yog ntev heev thiab lub zog siv.

Ua tsis tiav tsis tiav

Yam khoom: hypoeutectoid steel, uas tsis yog-loj nrog irregularities.

Lub hom phiaj: kev sib tsoo thiab muag muag ntawm pearlite grain, tsis hloov hloov ferrite.

Tshuab. Cua sov hlau mus rau ib tug kub ntog nyob rau hauv cov kis ntawm tus tseem ceeb heev cov ntsiab lus _Ac1 thiab _AC3. Extraction of blanks hauv lub cub tawg uas muaj cov yam ntxwv zoo yuav pab kom tiav cov txheej txheem tsim nyog. Txias ua tiav qeeb qeeb, nrog rau qhov cub. Ntawm cov zis, tib pearlite-ferritic nplua-grained qauv tau. Nrog rau qhov cua txias no, cov perlite yog hloov mus rau hauv nplua-grained, ferrite seem unchanged crystallically, thiab muaj peev xwm tsuas yog sib txawv structurally, tseem sib tsoo.

Kev tsis ua tiav ntawm cov hlau tso cai rau koj kom sib npaug hauv lub xeev thiab cov khoom ntawm cov khoom yooj yim, nws tsawg zog-intensive.

Tsawg tshaj tawm (recrystallization)

Yam khoom: tag nrho cov hom ntawm kuav los tiag carbon steel, hlau steel nrog ib tug carbon cov ntsiab lus ntawm 0,65% (e.g., pob tau cov kabmob), thiab dawb paug qhov chaw ua los ntawm nonferrous co uas tsis muaj lub sij hawm ntev nrog tsis xws luag, tab sis yuav tsum tau uas tsis yog-zog kho.

Hom phiaj:

• Tshem tawm ntawm kev ntxhov siab thiab kev ua hauj lwm vim tias muaj kev kub ntxhov thiab sov cev;
• Liquidation ntawm qhov tsis zoo ntawm kev tsis sib luag ntawm cov pob txha welded, nce zais thiab lub zog ntawm cov pob qij txha;
• Homogeneity ntawm lub microstructure ntawm cov khoom hlau uas tsis ferrous metallurgy;
• Spheroidization ntawm lamellar perlite - muab nws ib daim ntawv ntau.

Tshuab.

Cua sov ntawm qhov chaw ua rau 50-100˚S hauv qab no _Ac1 tseem ceeb heev point. Nyob rau hauv kev cuam tshuam ntawm xws li influences, me me hauv cov kev hloov yog tshem tawm. Tag nrho cov txheej txheem siv sijhawm siv sijhawm li 1-1.5 teev. Qhov tseem ceeb ntawm kev kub ntxhov rau ib co ntaub ntawv:

1. Cov hlau phom thiab tooj liab yog 600-700 ° C.
2. Nickel alloys - 800-1200 ° C.
3. Aluminium alloys - 300-450˚S.

Cua txias tau ua pa. Rau martensitic thiab bainitic hlau, technology ntawm cov hlau muab ib lub npe txawv rau txoj kev no - high tempering. Nws yog ib qho yooj yooj yim thiab pheej yig tshaj los txhim kho cov khoom ntawm cov khoom thiab cov khoom.

Homogenization (diffusion annealing)

Chaw: loj casting khoom, tshwj xeeb tshaj yog ntawm nrum stainless hlau.

Lub hom phiaj: kev sib koom tes ntawm kev sib txuam ntawm cov xaim alloying raws cov crystal lattices thiab tag nrho ntim cov ingot vim high-temperature diffusion; Softening tus qauv ntawm cov billet, txo nws cov hardness ua ntej yuav ua tiav cov kev ua hauj lwm tom ntej.

Tshuab. Cov khoom yog rhuab mus txog high kub ntawm 1000-1200 ° C. Kev ruaj ntseg thermal cov yam ntxwv yuav tsum tau ceev cia rau ib lub sij hawm ntev - txog 10-15 teev, nyob ntawm seb qhov loj me thiab tsis yooj yim ntawm cov qauv cam khwb cia. Tom qab ua tiav tag nrho cov theem ntawm cov kev hloov hauv high-temperature, qeeb txias hauv qab no.

Laborious, txawm li cas los, txheej txheem sib npaug ntawm kev sib npaug ntawm cov qauv loj.

Isothermal txoj kev sib tw

Khoom siv: daim ntawv hlau ntawm carbon hlau, cov khoom ntawm alloyed thiab high-alloyed alloys.

Lub Hom Phiaj: kom txhim kho cov kev tshawb fawb, tshem tawm tsis xws luag nrog tsawg lub sijhawm.

Tshuab. Cov hlau yog pib chiv rau tag nrho cov kev kub ntxhov thiab tostands lub sij hawm tsim nyog rau kev hloov ntawm tag nrho cov khoom muaj nyob rau hauv austenite. Tom qab ntawd maj mam txias los ntawm immersion nyob rau hauv liab kub ntsev. By tau raws li thaum tshav kub kub 50-100˚S rau hauv qab no lub _Ac1 point yog muab tso rau hauv ib lub cub tawg nyob rau hauv thiaj li yuav muaj nws nyob rau theem no thaum lub sij hawm lub sij hawm tsim nyog rau tag nrho transformation ntawm austenite rau pearlite thiab cementite. Thaum kawg haus txias yuav siv nyob rau hauv cov huab cua.

Txoj kev tso cai kom ua tiav cov khoom tsim nyog los ntawm cov hlau phom, thaum txuag lub sij hawm, sib piv nrog kev txheeb kom tiav.

Kev hloov cev

Khoom siv: castings, forgings thiab cov ntsiab lus los ntawm qis-carbon, medium-carbon thiab low-alloy steel.

Lub hom phiaj: kev sab hauv lub xeev, muab qhov nyuaj thiab lub zog xav, kev txhim kho hauv lub xeev ua ntej cov theem tom ntej ntawm kev kho kom sov thiab txiav.

Tshuab. Cov pa kub yog rhaub kom txias me ntsis saum lub kab GSE thiab nws cov ntsiab lus tseem ceeb, soak thiab txias hauv huab cua. Yog li, qhov kev ua tiav ntawm kev ua tiav nce. Txawm li cas los xij, nrog rau tus txheej txheem no nws muaj peev xwm ua kom tiav ib qho qauv uas ntsiag to xwb yog tias qhov muaj pes tsawg leeg ntawm cov hlau yog txiav txim siab los ntawm cov pa roj carbon rau qhov tsis ntau tshaj 0.4%. Nrog rau qhov nce ntawm cov pa roj carbon monoxide, qhov kev nce hauv kev ua kom raug. Tib lub hlau tom qab normalization muaj kev yawm suab ua ke nrog nrog tus npaug ntawm cov pob txha me me. Cov txheej txheem ua rau nws muaj peev xwm ua rau kom cov kab mob ntawm cov pob txha los ua kom tawg thiab ua raws li kev txiav ua haujlwm.

Tej zaum muaj kev tsis sib thooj

Thaum lub sij hawm tua ntawm tshav kub kev kho mob ua hauj lwm tsim nyog ua raws li predetermined hom kub cua kub thiab cua txias. Yog tias muaj kev yuam cai ntawm kev ua txhaum, muaj ntau yam teeb meem tshwm sim.

1. Oxidation ntawm txheej txheej thiab tsim ntawm cov nplai. Thaum lub sijhawm ua haujlwm, cov pa taws ua rau cov pa oxygen, uas ua rau lub qhov nplai ntawm qhov chaw ua haujlwm. Nws yuav tsum tau ntxuav tu txhua tus los yog nrog kev pab ntawm cov tshuaj reagents tshwj xeeb.
2. Burnout ntawm carbon. Kuj pom tshwm sim los ntawm cov nyhuv ntawm cov pa oxygen ntawm cov hlau kub. Txo cov nqi ntawm cov pa roj carbon dioxide nyob rau hauv cov txheej hlau ua rau kev txo qis rau nws cov khoom siv thiab cov khoom siv hauv tshuab. Yuav kom tiv thaiv cov txheej txheem, hlau kev txhav yuav tsum tau ua kom tiav nrog qhov kev qhia txog cov cua nkev rau hauv qhov cub, qhov haujlwm tseem ceeb ntawm kev tiv thaiv kom muaj kev cuam tshuam ntawm cov alloy nrog cov pa.
3. Overheating. Nws yog lub txiaj ntsig ntawm lub sij hawm ntev nyob rau hauv lub tshuab ua kom sov siab. Nws muaj lub txiaj ntsig ntawm kev loj hlob ntawm cov khoom nplej, qhov pib ntawm ib qhov kev sib txawv ntawm qhov sib xyaw, ua kom muaj brittleness. Nws yog kho los ntawm kev ua tiav ib theem ntxiv ntawm kev ua tiav.
4. Hlawv. Tshwm sim los ntawm ntau tshaj qhov tso cai qhov tseem ceeb ntawm cov cua sov thiab soaking, ua rau kev puas tsuaj ntawm cov qoob loo ntawm ib co nplej, tag nrho spoils tag nrho tus qauv ntawm cov hlau thiab tsis raug kho.

Txhawm rau tiv thaiv kev ua haujlwm, nws yog ib qho tseem ceeb kom paub tseeb tias kev kho mob kub yau, muaj kev txawj ntse thiab tswj hwm txoj kev.

Kev tawg ntawm txoj hlua yog ib lub tshuab ua tau yooj yim ntawm kev ua kom tiav cov kev lag luam ntawm qhov sib txawv ntawm qhov sib txawv thiab qhov muaj pes tsawg leeg rau qhov zoo tshaj plaws sab hauv thiab lub xeev uas yuav tsum tau ua rau cov theem tom qab ntawm thermal influences, txiav thiab commissioning ntawm tus qauv.