KUSIYANA PAKATI PA BK, GBK, BKS, NBK MU zitsulo.

KUSIYANA PAKATI PA BK, GBK, BKS, NBK MU zitsulo.

ABSTRACT:

Annealing ndi normalizing zitsulo ndi njira ziwiri wamba kutentha kutentha.
Cholinga choyambirira cha chithandizo cha kutentha: kuthetsa zolakwika zina zomwe zikusowekapo ndi zinthu zomwe zatha, ndikukonzekeretsa bungwe kuti lizigwira ntchito mozizira komanso kutentha komaliza.
Cholinga chomaliza cha chithandizo cha kutentha: kupeza ntchito yofunikira ya workpiece.
Cholinga cha annealing ndi normalizing ndi kuthetsa zofooka zina chifukwa cha kutentha processing zitsulo, kapena kukonzekera wotsatira kudula ndi chomaliza kutentha mankhwala.

 Kusintha kwa chuma:
1. Lingaliro: Njira yochizira kutentha yotenthetsera zida zachitsulo ku kutentha koyenera (pamwamba kapena pansi pa Ac1), kuzisunga kwa nthawi inayake, kenako kuziziritsa pang'onopang'ono kuti mupeze mawonekedwe oyandikana nawo kumatchedwa annealing.
2. Cholinga:
(1) Kuchepetsa kuuma ndi kukonza pulasitiki
(2) Yenga mbewu ndikuchotsa zolakwika zamapangidwe
(3) Kuthetsa kupsinjika kwamkati
(4) Konzekerani gulu kuti lizimitse
Mtundu: (Malinga ndi kutentha kwa kutentha, imatha kugawidwa m'mwamba kapena pansi pa kutentha kwakukulu (Ac1 kapena Ac3) Yoyamba imatchedwanso gawo kusintha recrystallization annealing, kuphatikizapo kutulutsa kwathunthu, kufalikira kwa homogenization annealing, kusakwanira, ndi spheroidizing annealing; Chotsatirachi chimaphatikizapo kubwezeretsanso kukonzanso ndi kuchepetsa nkhawa.)

•  Kukonzekera kwathunthu (GBK+A) :

1) Lingaliro: Kutenthetsa chitsulo cha hypoeutectoid (Wc = 0.3% ~ 0.6%) mpaka AC3 + (30 ~ 50) ℃, ndipo chikatsimikiziridwa kwathunthu, kuteteza kutentha ndi kuzizira pang'onopang'ono (motsatira ng'anjo, kukwirira mu mchenga, laimu), Njira yochizira kutentha kuti mupeze mawonekedwe oyandikana ndi malo ofananirako amatchedwa annealing wathunthu.2) Cholinga: Yenga mbewu, mawonekedwe ofanana, kuthetsa kupsinjika kwamkati, kuchepetsa kuuma, ndikuwongolera magwiridwe antchito.
2) Njira: kuziziritsa kwathunthu ndi kuziziritsa pang'onopang'ono ndi ng'anjo kumatha kuwonetsetsa kuti mpweya wa proeutectoid ferrite komanso kusintha kwa supercooled austenite kukhala pearlite pa kutentha kwakukulu pansi pa Ar1.The akugwira ntchito workpiece pa kutentha annealing osati zimapangitsa workpiece kuwotcha kudzera, ndiko kuti, pachimake workpiece kufika chofunika Kutentha kutentha, komanso amaonetsetsa kuti onse homogenized austenite zikuoneka kukwaniritsa recrystallization wathunthu.Nthawi yogwira annealing wathunthu ikugwirizana ndi zinthu monga zitsulo kapangidwe, workpiece makulidwe, ng'anjo kudzaza mphamvu ndi ng'anjo yotsegula njira.Pakupanga kwenikweni, kuti muwonjezere zokolola, kuziziritsa ndi kuziziritsa pafupifupi 600 ℃ kungakhale kunja kwa ng'anjo ndi kuziziritsa mpweya.
Kuchuluka kwa ntchito: kuponyera, kuwotcherera, kupangira ndi kugudubuza kwa sing'anga kaboni chitsulo ndi sing'anga mpweya aloyi zitsulo, ndi zina zotero.Kuuma kwa chitsulo chochepa cha carbon ndi chochepa pambuyo pa kutsekedwa kwathunthu, zomwe sizingathandize kudula processing.Chitsulo cha hypereutectoid chikatenthedwa ku dziko la austenite pamwamba pa Accm ndikukhazikika pang'onopang'ono ndikumangirira, makina a simenti yachiwiri amawotchedwa, omwe amachepetsa kwambiri mphamvu, pulasitiki komanso kulimba kwachitsulo.

• Spheroidizing annealing:

1) Lingaliro: Njira yopangira ma spheroidize carbides muzitsulo imatchedwa spheroidizing annealing.
2) Njira: General spheroidizing annealing process Ac1+(10~20) ℃ yaziziritsidwa ndi ng'anjo mpaka 500 ~ 600 ℃ ndi kuziziritsa kwa mpweya.
3) Cholinga: kuchepetsa kuuma, kukonza bungwe, kukonza pulasitiki ndi ntchito yodula.
4) Kuchuluka kwa ntchito: makamaka ntchito zida kudula, zida kuyeza, zisamere pachakudya, etc. zitsulo eutectoid ndi hypereutectoid zitsulo.Pamene chitsulo cha hypereutectoid chili ndi makina a cementite yachiwiri, sichingokhala ndi kuuma kwakukulu ndipo n'kovuta kuchita kudula, komanso kumawonjezera kuphulika kwachitsulo, komwe kumakhala kosavuta kuzimitsa mapindikidwe ndi kusweka.Pachifukwa ichi, spheroidizing annealing ndondomeko ayenera kuwonjezeredwa pambuyo yotentha ntchito zitsulo kuti spheroidize flake kulowa mu reticulated sekondale cementite ndi pearlite kupeza granular pearlite.
Kuzizira komanso kutentha kwa isothermal kudzakhudzanso zotsatira za carbide spheroidization.Kuzizira kofulumira kapena kutentha kwa isothermal kumapangitsa kuti pearlite ipangidwe pakutentha kochepa.Ma carbide particles ndiabwino kwambiri ndipo kuphatikizikako kumakhala kochepa, zomwe zimapangitsa kuti zikhale zosavuta kupanga ma carbides.Zotsatira zake, kuuma kumakhala kwakukulu.Ngati kuziziritsa kugunda kwambiri wodekha kapena isothermal kutentha kwambiri, ndi carbide particles anapanga adzakhala coarser ndi zotsatira agglomeration adzakhala amphamvu kwambiri.Ndizosavuta kupanga ma carbides a granular makulidwe osiyanasiyana ndikupangitsa kuuma kwake kukhala kochepa.

•  Homogenization annealing (kufalikira kwa annealing):

1) Njira: Kutentha kwa kutentha kwa kutentha kwazitsulo zazitsulo zazitsulo kapena zoponyera mpaka 150 ~ 00 ℃ pamwamba pa Ac3, kugwira kwa 10 ~ 15h ndiyeno kuziziritsa pang'onopang'ono kuthetsa kusiyana kwa mankhwala.
2) Cholinga: Chotsani tsankho la dendrite panthawi ya crystallization ndi homogenize zomwe zilipo.Chifukwa cha kutentha kwakukulu komanso nthawi yayitali, njere za austenite zimakhala zouma kwambiri.Chifukwa chake, nthawi zambiri pamafunika kuwongolera kwathunthu kapena kukhazikika kuti muyese njere ndikuchotsa zolakwika zotentha kwambiri.
3) Kuchuluka kwa ntchito: makamaka amagwiritsidwa ntchito pazitsulo zazitsulo za alloy, castings ndi forgings ndi zofunika kwambiri.
4) Zindikirani: Kutentha kwa kutentha kwakukulu kumakhala ndi nthawi yayitali yopanga, kugwiritsira ntchito mphamvu zambiri, makutidwe ndi okosijeni kwambiri ndi decarburization ya workpiece, ndi kukwera mtengo.Zitsulo zamtundu wapamwamba wa alloy ndi zitsulo za alloy castings ndi ingots zachitsulo zokhala ndi tsankho lalikulu zimagwiritsa ntchito njirayi.Kwa ma castings ang'onoang'ono ang'onoang'ono kapena zitsulo za kaboni, chifukwa cha kusiyana kwawo mopepuka, annealing wathunthu angagwiritsidwe ntchito kuyeretsa mbewu ndikuchotsa kupsinjika.

• Kuchepetsa kupsinjika

1) Lingaliro: Annealing kuchotsa kupsyinjika chifukwa pulasitiki deformation processing, kuwotcherera, etc. ndi otsala kupsyinjika mu kuponyera amatchedwa stress relief annealing.(Palibe kupotoza komwe kumachitika panthawi yochepetsera nkhawa)
2) Njira: pang'onopang'ono kutentha workpiece 100 ~ 200 ℃ (500 ~ 600 ℃) pansi Ac1 ndi kusunga kwa nthawi (1 ~ 3h), kenako kuziziziritsa pang'onopang'ono mpaka 200 ℃ ndi ng'anjo, kenako ozizira. izo kuchokera mu ng'anjo.
Chitsulo nthawi zambiri chimakhala 500 ~ 600 ℃
Chitsulo chotaya nthawi zambiri chimaposa 550 buckles pa 500-550 ℃, zomwe zingayambitse graphitization ya pearlite mosavuta.Zigawo zowotcherera nthawi zambiri zimakhala 500 ~ 600 ℃.
3) Kuchuluka kwa ntchito: Chotsani kupsinjika kotsalira pazigawo zoponyedwa, zopukutira, zowotcherera, zida zoziziritsa zozizira ndi zida zamakina kuti zikhazikitse kukula kwazigawo zachitsulo, kuchepetsa kupunduka komanso kupewa kusweka.

Normalizing zitsulo:
1. Lingaliro: kutentha chitsulo ku 30-50 ° C pamwamba pa Ac3 (kapena Accm) ndikuchigwira kwa nthawi yoyenera;njira yochizira kutentha kwa kuziziritsa mu mpweya wokhazikika imatchedwa normalizing of steel.
2. Cholinga: Yenga mbewu, mawonekedwe ofanana, kusintha kuuma, etc.
3. Bungwe: Eutectoid steel S, hypoeutectoid steel F+S, hypereutectoid steel Fe3CⅡ+S
4. Njira: Nthawi yosungira kutentha ndi yofanana ndi annealing kwathunthu.Ziyenera kukhazikitsidwa pa workpiece kudzera kuwotcha, ndiko kuti, pachimake chimafika pa kutentha kwa kutentha kofunikira, ndi zinthu monga chitsulo, mapangidwe oyambirira, mphamvu ya ng'anjo ndi zipangizo zotentha ziyenera kuganiziridwanso.Njira yoziziritsira yomwe imagwiritsidwa ntchito kwambiri ndikuchotsa chitsulo mu ng'anjo yotenthetsera ndikuziziritsa mwachilengedwe mumlengalenga.Pazigawo zazikulu, kuwomba, kupopera mbewu mankhwalawa ndi kusintha mtunda wa stacking wa mbali zachitsulo zingagwiritsidwenso ntchito kuwongolera kuzizira kwa zigawo zachitsulo kuti zikwaniritse bungwe lofunikira ndi ntchito.

5. Ntchito zosiyanasiyana:

• 1) Sinthani magwiridwe antchito achitsulo.Chitsulo cha kaboni ndi chitsulo chochepa cha alloy chokhala ndi mpweya wochepera 0.25% chimakhala ndi kuuma kochepa pambuyo pa annealing, ndipo ndizosavuta "kumamatira" panthawi yodula.Kupyolera mu chithandizo chokhazikika, ferrite yaulere imatha kuchepetsedwa ndipo pearlite ya flake imatha kupezeka.Kuchulukitsa kuuma kumatha kusintha machinability chitsulo, kuwonjezera moyo wa chida ndi pamwamba mapeto a workpiece.
• 2) Chotsani zolakwika zopangira mafuta.Zopangira zitsulo zopangidwa ndi mpweya wapakatikati, zomangira, zopindika ndi zida zowotcherera zimatha kukhala ndi zolakwika zowotcha komanso zomangira zomangira monga njere zolimba zikatenthedwa.Kupyolera mu mankhwala ochiritsira, zowonongeka zowonongeka zimatha kuthetsedwa, ndipo cholinga cha kukonzanso kwambewu, kapangidwe ka yunifolomu ndi kuthetsa kupsinjika kwamkati kungatheke.
• 3) Chotsani ma network a carbides a hypereutectoid zitsulo, ndikuwongolera spheroidizing annealing.Chitsulo cha hypereutectoid chiyenera kukhala spheroidized ndi annealed pamaso kuzimitsa kuti atsogolere Machining ndi kukonzekera dongosolo quenching.Komabe, pakakhala ma network carbides mu hypereutectoid steel, zotsatira zabwino za spheroidizing sizingachitike.Net carbide imatha kuthetsedwa ndi chithandizo chamankhwala.
• 4) Kupititsa patsogolo makina azinthu zodziwika bwino.Zina zazitsulo za carbon ndi alloy zitsulo zokhala ndi kupsinjika pang'ono ndi zofunikira zochepa zogwirira ntchito zimasinthidwa kuti zitheke kukwaniritsa makina ambiri, omwe angalowe m'malo mwa kuzimitsa ndi kutentha monga chithandizo chomaliza cha kutentha kwa zigawozo.

Kusankha annealing ndi normalizing
Kusiyana kwakukulu pakati pa annealing ndi normalizing:
1. Kuzizira kwa kuzizira kumathamanga pang'ono kusiyana ndi kuzizira, ndipo kuzizira kwapansi kumakhala kwakukulu.
2. Kapangidwe kamene kamapezeka pambuyo pa normalizing ndi bwino, ndipo mphamvu ndi kuuma ndi apamwamba kuposa annealing.Kusankha annealing ndi normalizing:

• Kwa chitsulo chochepa cha carbon chokhala ndi carbon <0,25%, normalizing imagwiritsidwa ntchito m'malo mwa annealing.Chifukwa kuzirala kwachangu kumatha kuletsa chitsulo chochepa cha mpweya kuti chisagwetse simenti yaufulu yapamwamba m'malire a tirigu, potero kuwongolera magwiridwe antchito ozizira a magawo opondapo;normalizing akhoza kusintha kuuma kwa chitsulo ndi ntchito kudula wa otsika mpweya zitsulo;Pochiza kutentha, normalizing angagwiritsidwe ntchito kuyenga njere ndi kupititsa patsogolo mphamvu ya low carbon zitsulo.
• Chitsulo chapakati cha kaboni chokhala ndi mpweya wapakati pa 0,25 ndi 0.5% chimathanso kukhala chokhazikika m'malo mwa annealing.Ngakhale kuuma kwa sing'anga mpweya zitsulo pafupi malire chapamwamba cha mpweya zili apamwamba pambuyo normalizing, akhoza kudulidwa ndi mtengo wa normalizing Low ndi mkulu zokolola.
• Chitsulo chokhala ndi kaboni pakati pa 0,5 ndi 0.75%, chifukwa cha kuchuluka kwa kaboni, kuuma pambuyo pa normalizing kumakhala kokulirapo kuposa komwe kumatulutsa, ndipo kumakhala kovuta kudula.Choncho, annealing kwathunthu amagwiritsidwa ntchito kuchepetsa kuuma ndi kukonza kudula.Kuthekera.
• Zitsulo zapamwamba za carbon kapena zitsulo zokhala ndi mpweya wambiri> 0.75% nthawi zambiri zimagwiritsa ntchito spheroidizing annealing ngati chithandizo choyambirira cha kutentha.Ngati pali netiweki ya simenti yachiwiri, iyenera kusinthidwa kaye.

Gwero:Mabuku aukadaulo wamakina.

Editor: Ali