1. Quenching
1. Dab tsi yog quenching?
Quenching yog txheej txheem kev kho cua sov siv rau cov hlau. Nyob rau hauv cov txheej txheem no, cov hlau yog rhuab mus rau qhov kub siab tshaj qhov tseem ceeb kub Ac3 (rau hypereutectoid steel) los yog Ac1 (rau hypereutectoid steel). Tom qab ntawd nws tau khaws cia ntawm qhov kub thiab txias rau ib lub sijhawm kom tag nrho lossis ib nrab austenitize cov hlau, thiab tom qab ntawd maj mam txias rau hauv qab Ms (los yog tuav isothermally ze Ms) ntawm tus nqi cua txias siab dua qhov tseem ceeb ntawm qhov txias txias kom hloov mus rau hauv martensite ( los yog bainite). quenching kuj yog siv rau cov khoom siv kho mob thiab kev ua kom txias sai ntawm cov ntaub ntawv xws li aluminium alloys, tooj liab alloys, titanium alloys, thiab tempered iav.
2. Lub hom phiaj ntawm quenching:
1) Txhim kho cov khoom siv hluav taws xob ntawm cov khoom siv hlau lossis cov khoom siv. Piv txwv li, nws txhim khu lub hardness thiab hnav tsis kam ntawm cov cuab yeej, bearings, thiab lwm yam, tsub kom lub elastic txwv ntawm springs, txhim kho tag nrho cov neeg kho tshuab zog ntawm ncej, thiab lwm yam.
2) Txhawm rau txhim kho cov khoom siv lossis tshuaj lom neeg ntawm cov hlau tshwj xeeb, xws li kev txhim kho corrosion tsis kam ntawm cov hlau tsis muaj steel lossis ua kom cov hlau nplaum ruaj khov ntawm cov hlau nplaum, nws yog ib qho tseem ceeb uas yuav tau ua tib zoo xaiv cov xov xwm quenching thiab siv txoj kev quenching kom raug thaum lub sij hawm. quenching thiab txias txheej txheem. Feem ntau siv quenching txoj kev muaj xws li ib leeg-kua quenching, ob-kua quenching, graded quenching, isothermal quenching, thiab hauv zos quenching. Txhua txoj kev muaj nws cov kev siv tshwj xeeb thiab cov txiaj ntsig.
3. Tom qab quenching, steel workpieces nthuav tawm cov yam ntxwv hauv qab no:
- Cov qauv tsis ruaj khov xws li martensite, bainite, thiab residual austenite tam sim no.
- Muaj kev ntxhov siab sab hauv.
- Cov khoom siv kho tshuab tsis ua raws li qhov yuav tsum tau ua. Yog li ntawd, steel workpieces feem ntau raug tempering tom qab quenching.
2. Tempering
1. Tempering yog dab tsi?
Tempering yog txheej txheem kev kho cua sov uas suav nrog cov khoom siv cua sov quenched hlau lossis qhov chaw rau qhov kub thiab txias, tswj qhov kub thiab txias rau qee lub sijhawm, thiab tom qab ntawd txias rau hauv ib qho tshwj xeeb. Tempering yog ua tam sim tom qab quenching thiab feem ntau yog cov kauj ruam kawg hauv kev kho cua sov ntawm lub workpiece. Cov txheej txheem ua ke ntawm quenching thiab tempering yog hu ua kev kho zaum kawg.
2. Lub hom phiaj tseem ceeb ntawm quenching thiab tempering yog:
- Tempering yog qhov tseem ceeb los txo cov kev ntxhov siab sab hauv thiab brittleness hauv quenched qhov chaw. Yog tias tsis tempered raws sijhawm, cov khoom no tuaj yeem deform lossis tawg vim muaj kev ntxhov siab thiab brittleness los ntawm quenching.
- Tempering kuj tuaj yeem siv los kho cov khoom siv kho tshuab ntawm cov khoom ua haujlwm, xws li hardness, lub zog, plasticity, thiab toughness, kom ua tau raws li cov kev xav tau sib txawv.
- Tsis tas li ntawd, tempering pab kom ruaj khov qhov loj ntawm lub workpiece los ntawm kev xyuas kom meej tias tsis muaj deformation tshwm sim thaum siv tom ntej, raws li nws stabilizes metallographic qauv.
- Tempering kuj tuaj yeem txhim kho kev ua haujlwm ntawm qee cov hlau alloy.
3. Lub luag haujlwm ntawm tempering yog:
Txhawm rau kom ntseeg tau tias lub workpiece tseem nyob ruaj khov thiab tsis muaj kev hloov pauv ntawm cov txheej txheem thaum siv, nws yog ib qho tseem ceeb los txhim kho qhov ruaj khov ntawm cov qauv. Qhov no suav nrog kev tshem tawm cov kev ntxhov siab sab hauv, uas nyob rau hauv lem yuav pab stabilize lub geometric qhov ntev thiab txhim kho kev ua tau zoo ntawm lub workpiece. Tsis tas li ntawd, tempering tuaj yeem pab kho cov khoom siv ntawm cov hlau kom ua tau raws li kev siv tshwj xeeb.
Tempering muaj cov teebmeem no vim tias thaum kub nce, qhov kev ua haujlwm atomic tau txhim kho, tso cai rau cov atoms ntawm hlau, carbon, thiab lwm yam hlau alloy hauv cov hlau kom nrawm dua. Qhov no ua rau lub rearrangement ntawm atoms, transforming lub unstable, unbalanced qauv rau hauv ib tug ruaj khov, balanced qauv.
Thaum cov hlau yog tempered, lub hardness thiab lub zog txo thaum lub plasticity nce. Qhov twg ntawm cov kev hloov pauv hauv cov khoom siv kho tshuab yog nyob ntawm qhov kub thiab txias, nrog rau qhov kub thiab txias ua rau muaj kev hloov pauv ntau dua. Hauv qee cov hlau alloys nrog cov ntsiab lus siab ntawm cov ntsiab lus alloying, tempering nyob rau hauv ib qho kub ntau yam tuaj yeem ua rau nag lossis daus ntawm cov hlau zoo. Qhov no nce lub zog thiab hardness, ib qho tshwm sim hu ua Secondary hardening.
Tempering xav tau: txawvmachined qhov chawyuav tsum tau tempering ntawm qhov kub sib txawv kom tau raws li kev siv tshwj xeeb. Nov yog qhov pom zoo tempering kub rau ntau hom workpieces:
1. Cov cuab yeej txiav, bearings, carburized thiab quenched qhov chaw, thiab nto quenched qhov chaw feem ntau yog tempered ntawm qhov kub thiab txias hauv qab 250 ° C. Cov txheej txheem no ua rau muaj kev hloov pauv tsawg kawg hauv hardness, txo cov kev ntxhov siab sab hauv, thiab kev txhim kho me ntsis hauv cov tawv tawv.
2. Springs yog tempered ntawm nruab nrab kub xws li ntawm 350-500 ° C kom ua tau siab dua elasticity thiab tsim nyog toughness.
3. Cov khoom ua los ntawm nruab nrab-carbon structural steel feem ntau yog tempered ntawm qhov kub thiab txias ntawm 500-600 ° C kom tau txais kev pom zoo ua ke ntawm lub zog thiab toughness.
Thaum cov hlau yog tempered nyob ib ncig ntawm 300 ° C, nws tuaj yeem ua nkig, qhov tshwm sim hu ua thawj hom temper brittleness. Feem ntau, tempering yuav tsum tsis txhob ua nyob rau hauv qhov ntsuas kub no. Qee qhov nruab nrab-carbon alloy cov qauv hlau kuj tseem ua rau brittleness yog tias lawv maj mam txias rau hauv chav sov tom qab kub kub, hu ua hom thib ob ntawm temper brittleness. Ntxiv molybdenum rau hlau los yog txias hauv cov roj los yog dej thaum lub sij hawm tempering tuaj yeem tiv thaiv ob hom temper brittleness. Reheating hom thib ob ntawm tempered brittle steel rau thawj tempering kub tuaj yeem tshem tawm qhov brittleness.
Hauv kev tsim khoom, qhov kev xaiv ntawm tempering kub nyob ntawm qhov kev ua tau zoo ntawm lub workpiece. Tempering yog categorized raws li cov cua kub sib txawv rau hauv qhov kub thiab txias, nruab nrab-kub tempering, thiab high-temperature tempering. Cov txheej txheem kev kho cua sov uas suav nrog quenching ua raws li qhov kub thiab txias yog hu ua tempering, ua rau lub zog siab, zoo plasticity, thiab toughness.
- Tsawg-kub tempering: 150-250 ° C, M tempering. Cov txheej txheem no txo cov kev ntxhov siab sab hauv thiab brittleness, txhim kho plasticity thiab toughness, thiab ua rau muaj zog dua thiab hnav tsis kam. Nws feem ntau yog siv los ua cov cuab yeej ntsuas, cov cuab yeej txiav, dov bearings, thiab lwm yam.
- Nruab nrab-kub tempering: 350-500 ° C, T tempering. Cov txheej txheem tempering no ua rau ntau dua elasticity, qee yam yas, thiab hardness. Nws yog feem ntau siv los tsim cov springs, forging tuag, thiab lwm yam.
- Kub-kub tempering: 500-650 ° C, S tempering. Cov txheej txheem no ua rau muaj txiaj ntsig zoo txhua yam thiab feem ntau yog siv los ua lub zog, crankshafts, thiab lwm yam.
3. normalizing
1. Dab tsi yog normalizing?
Covcnc kevntawm normalizing yog kev kho cua sov siv los txhim kho lub toughness ntawm hlau. Cov hlau tivthaiv yog rhuab mus rau qhov kub ntawm 30 txog 50 ° C saum toj no qhov kub ntawm Ac3, tuav ntawm qhov kub ntawm lub sijhawm, thiab tom qab ntawd cua txias sab nraum lub cub tawg. Normalizing yuav ua kom txias sai dua li annealing tab sis qeeb txias dua li quenching. Cov txheej txheem no ua rau cov pob zeb ua kom zoo nkauj hauv cov hlau, txhim kho lub zog, toughness (raws li qhia los ntawm tus nqi AKV), thiab txo cov khoom tiv thaiv kom tawg. Normalizing tuaj yeem txhim kho cov khoom siv dav dav ntawm cov hlau tsis tshua muaj hlau kub-kuav los tiag steel phaj, qis-alloy steel forgings, thiab castings, nrog rau kev txhim kho kev ua haujlwm.
2. Normalizing muaj cov hom phiaj thiab siv hauv qab no:
1. Hypereutectoid steel: Normalizing yog siv los tshem tawm overheated coarse-grained thiab Widmanstatten cov qauv hauv castings, forgings, thiab weldments, nrog rau cov qauv banded hauv cov ntaub ntawv dov. Nws refines cov nplej thiab yuav siv tau raws li ib tug pre-heat kev kho mob ua ntej quenching.
2. Hypereutectoid steel: Normalizing tuaj yeem tshem tawm lub network thib ob cementite thiab ua kom zoo pearlite, txhim kho cov khoom siv kho tshuab thiab ua kom yooj yim spheroidizing annealing tom qab.
3. Tsawg-carbon, sib sib zog nqus-kos nyias hlau daim hlau: Normalizing tuaj yeem tshem tawm cov cementite dawb ntawm thaj tsam lis, txhim kho kev sib sib zog nqus kos duab.
4. Tsawg-carbon steel thiab low-carbon low-alloy steel: Normalizing yuav tau finer, flaky pearlite lug, nce hardness rau HB140-190, zam lub "sticking riam" tshwm sim thaum txiav, thiab kev txhim kho machinability. Nyob rau hauv cov xwm txheej uas ob qho tib si normalizing thiab annealing yuav siv tau rau nruab nrab-carbon steel, normalizing yog ntau yig thiab yooj yim.
5. Ordinary nruab nrab-carbon structural steel: Normalizing yuav siv tau es tsis txhob ntawm quenching thiab high-temperature tempering thaum lub siab mechanical zog tsis xav tau, ua cov txheej txheem yooj yim thiab ua kom ruaj khov steel qauv thiab loj.
6. High-temperature normalizing (150-200 ° C saum Ac3): Txo cov khoom sib cais ntawm cov castings thiab forgings vim muaj qhov sib txawv ntawm qhov kub thiab txias. Coarse nplej tuaj yeem ua kom zoo dua los ntawm qhov thib ob tom ntej normalizing ntawm qhov kub thiab txias.
7. Tsawg- thiab nruab nrab-carbon alloy steels siv nyob rau hauv chav turbines thiab boilers: Normalizing yog siv kom tau ib tug bainite qauv, ua raws li high-temperature tempering rau zoo creep kuj ntawm 400-550 ° C.
8. Ntxiv rau cov khoom siv hlau thiab cov khoom siv hlau, normalizing kuj yog siv dav hauv kev kho cua sov ntawm cov hlau nplaum kom tau txais pearlite matrix thiab txhim kho lub zog ntawm cov hlau ductile. Cov yam ntxwv ntawm normalizing muaj cua txias, yog li lub ambient kub, stacking txoj kev, airflow, thiab workpiece loj tag nrho cov muaj feem xyuam rau cov qauv thiab kev ua tau zoo tom qab normalizing. Cov qauv normalizing kuj tseem siv tau los ua ib txoj kev faib rau cov hlau alloy. Feem ntau, cov hlau alloy yog categorized rau hauv pearlite steel, bainite steel, martensite steel, thiab austenite steel, nyob ntawm seb cov qauv tau los ntawm huab cua txias tom qab cua sov cov qauv nrog ib txoj kab uas hla ntawm 25 hli mus rau 900 ° C.
4. Annealing
1. Dab tsi yog annealing?
Annealing yog txheej txheem kev kho cua sov rau hlau. Nws koom nrog maj mam cua sov cov hlau mus rau qhov kub thiab txias, tswj nws ntawm qhov kub thiab txias rau ib lub sijhawm, thiab tom qab ntawd txias nws ntawm tus nqi tsim nyog. Annealing tuaj yeem categorized rau ua tiav annealing, tsis tiav annealing, thiab kev ntxhov siab annealing. Cov khoom siv ntawm cov khoom siv annealed tuaj yeem ntsuas los ntawm kev ntsuas tensile lossis kev sim hardness. Ntau cov hlau tau muab rau hauv lub xeev annealed. Hlau hardness tuaj yeem ntsuas tau siv Rockwell hardness tester, uas ntsuas HRB hardness. Rau cov hlau nyias nyias, cov hlua hlau, thiab cov kav hlau nyias nyias, lub ntsej muag Rockwell hardness tester tuaj yeem siv los ntsuas HRT hardness.
2. Lub hom phiaj ntawm annealing yog:
- Txhim kho lossis tshem tawm ntau yam kev ua haujlwm tsis zoo thiab cov kev ntxhov siab uas tshwm sim los ntawm cov hlau hauv cov casting, forging, dov, thiab vuam txheej txheem los tiv thaiv deformation thiab tawg ntawmtuag casting qhov chaw.
-Soften lub workpiece rau txiav.
- Txhim kho cov nplej thiab txhim kho cov qauv txhawm rau txhim kho cov khoom siv kho tshuab ntawm cov khoom ua haujlwm.
- Npaj cov qauv rau kev kho cua sov zaum kawg (quenching thiab tempering).
3. Cov txheej txheem annealing feem ntau yog:
① Ua kom tiav annealing.
Txhawm rau txhim kho cov cuab yeej cuab tam ntawm nruab nrab thiab qis carbon steel tom qab casting, forging, thiab vuam, nws yog ib qho tsim nyog yuav tsum ua kom zoo dua cov txheej txheem coarse overheated. Cov txheej txheem suav nrog cua sov lub workpiece mus rau qhov kub ntawm 30-50 ℃ siab tshaj qhov taw tes uas tag nrho cov ferrite hloov mus rau hauv austenite, tswj qhov kub ntawm lub sijhawm, thiab tom qab ntawd maj mam txias lub workpiece hauv qhov cub. Raws li lub workpiece txias, lub austenite yuav hloov dua siab tshiab, uas ua rau lub finer steel qauv.
② Spheroidizing annealing.
Txhawm rau txo qhov nyuaj ntawm cov cuab yeej hlau thiab cov kabmob hlau tom qab forging, koj yuav tsum tau ua kom sov lub workpiece mus rau qhov kub ntawm 20-40 ℃ siab tshaj qhov uas cov hlau pib tsim austenite, ua kom sov, thiab maj mam txias nws maj mam. Raws li lub workpiece txias, lamellar cementite nyob rau hauv lub pearlite hloov mus rau hauv ib tug kheej kheej, uas txo cov hardness ntawm hlau.
③ Isothermal annealing.
Cov txheej txheem no yog siv los txo cov hardness siab ntawm tej yam hlau alloy steels siab nickel thiab chromium cov ntsiab lus rau kev txiav. Feem ntau, cov hlau tau txias sai heev rau qhov tsis ruaj khov tshaj plaws ntawm austenite thiab tom qab ntawd tuav ntawm qhov sov sov rau lub sijhawm tshwj xeeb. Qhov no ua rau austenite hloov mus rau hauv troostite lossis sorbite, uas ua rau txo qis ntawm hardness.
④ Recrystallization annealing.
Cov txheej txheem yog siv los txo cov hardening ntawm hlau hlau thiab nyias daim hlau uas tshwm sim thaum lub caij txias txias thiab txias dov. Cov hlau yog rhuab mus rau qhov kub uas feem ntau yog 50-150 ℃ hauv qab qhov taw tes uas cov hlau pib tsim austenite. Qhov no tso cai rau kev tshem tawm cov teebmeem ua haujlwm hnyav thiab softens cov hlau.
⑤ Graphitization annealing.
Txhawm rau hloov cov cam khwb cia hlau nrog cov ntsiab lus siab ntawm cov cementite rau hauv forgeable cam khwb cia hlau nrog cov yas zoo, cov txheej txheem yuav tsum ua kom sov lub casting rau ib ncig ntawm 950 ° C, tswj qhov kub thiab txias rau ib lub sij hawm tshwj xeeb, thiab tom qab ntawd txias nws kom tsim nyog los rhuav tshem cov cementite thiab tsim flocculent graphite.
⑥ Diffusion annealing.
Cov txheej txheem yog siv los txawm tawm cov tshuaj muaj pes tsawg leeg ntawm alloy castings thiab txhim khu lawv kev ua tau zoo. Cov txheej txheem suav nrog cua sov lub casting mus rau qhov kub siab tshaj plaws uas tsis muaj melting, tswj qhov kub thiab txias rau lub sijhawm ntev, thiab maj mam txias nws. Qhov no tso cai rau ntau yam ntsiab lus nyob rau hauv lub alloy kom diffuse thiab ua uniformly faib.
⑦ Kev ntxhov siab rau kev ntxhov siab.
Cov txheej txheem no yog siv los txo cov kev ntxhov siab sab hauv hauv steel castings thiab welded qhov chaw. Rau cov khoom siv hlau uas pib tsim austenite tom qab cua sov ntawm qhov kub ntawm 100-200 ℃ hauv qab no, lawv yuav tsum tau khaws cia kom sov thiab txias hauv huab cua kom tshem tawm cov kev ntxhov siab sab hauv.
Yog tias koj xav paub ntau ntxiv lossis nug, thov hu rau dawbinfo@anebon.com.
Qhov zoo ntawm Anebon yog cov nqi qis dua, pab pawg cov nyiaj tau los zoo, QC tshwj xeeb, cov chaw tsim khoom ruaj khov, cov kev pabcuam zoo raualuminium machining kev pabcuamthiabcnc machining qhov chawua kev pabcuam. Anebon tau teeb tsa lub hom phiaj ntawm Kev Txhim Kho Kev Txhim Kho Kev Lag Luam, kev tswj hwm kev tsim kho tshiab, cov neeg tseem ceeb innovation thiab kev tsim kho tshiab, muab kev ua si tag nrho rau qhov zoo ntawm tag nrho, thiab niaj hnub ua kev txhim kho kom txhawb nqa zoo.
Post lub sij hawm: Aug-14-2024