Quenching yog cov kauj ruam tseem ceeb tshaj plaws hauv kev kho cua sov steel.
Hauv cov ntsiab lus yooj yim:
Tshav kub cov hlau mus rau xim liab-kub lub xeev (nrog nws cov qauv sab hauv hloov mus rau hauv "austenite"), tom qab ntawd maj mam txias nws (rau hauv dej / roj / lwm yam nruab nrab), tiv thaiv cov qauv sab hauv los ntawm "them reverting" thiab xauv nws mus rau hauv ib qho nyuaj thiab nkig "martensite".
Kev rhuav tshem nws, nws muaj peb yam kev ua:
- Cua sov (austenitization)- Tshav kub ntawm cov hlau mus txog 800-950 degree, ua rau cov atoms sab hauv los hloov kho rau hauv cov qauv kub "austenite". Qhov no yog qhov yuav tsum tau ua ua ntej; qhov kub tsis txaus txhais tau hais tias nws yog qhov nkim sijhawm.
- tuav - Cia lub cua sov nkag mus rau hauv cov tub ntxhais kom paub meej tias tag nrho cov khoom yog kom huv si thiab cov qauv zoo ib yam.
- Rapi cua txias- Qhov no yog lub ntsiab lus ntawm lo lus "quenching". Qhov tseem ceeb yog ceev: txias nws hauv vib nas this mus rau kaum vib nas this. Tsis muaj sij hawm txaus rau cov pa roj carbon atoms rov- faib thiab npaj rau hauv cov ntaub so ntswg (lamellar pearlite / ferrite), yog li cov atoms yog "khov" nyob rau hauv ib qho oversaturated, distorted lattice, uas yog martensite - nws yog ib qho nyuaj heev tab sis kuj tsis tshua muaj nkig.
Piv txwv li: Ib yam li boiling ib lub lauj kaub dej (austenitization), yog tias nws tso cai rau txias lawm, nws yuav tsim cov dej khov tsis tu ncua (cov ntaub so ntswg mos); Yog tias nws tau khov tam sim ntawd los ntawm kev nchuav nws rau hauv cov kua nitrogen, cov dej molecules tsis tuaj yeem teem caij thiab tsim cov dej khov tsis zoo (martensite). Quenching yog zoo li "tam sim no khov".
Cov khoom tseem ceeb:
- Tom qab quenching, cov hlau yuav nyuaj, muaj zog, thiab hnav ntau dua -resistant (ua tsaug rau martensite).
- Tab sis nws kuj ua nkig thiab muaj kev ntxhov siab sab hauv, ua rau nws yooj yim tawg thaum siv ncaj qha.
- Yog li ntawd, quenching yuav luag tsis siv ib leeg; Nws yuav tsum tau ua raws li tam sim ntawd los ntawm cov txheej txheem tempering (reheating ntawm qhov kub thiab txias thiab tuav ib pliag), kom txo brittleness thiab sab hauv kev ntxhov siab thiab rov qab toughness. quenching + tempering=tempering kho, uas yog qhov tseeb siv hauv engineering.
Yog li nco ntsoov ib tug mnemonic:
Quenching yog "hardening", tempering yog "rescuing brittleness", lawv yog ib khub, ob qho tib si indispensable.
Yuav ua li cas tempering?
Cov txheej txheem ntawm tempering yog ntau "gentler" dua li quenching - tsis tas yuav kom txias ceev. Qhov tseem ceeb tsis yog peb: tempering kub, tuav lub sij hawm, thiab txias txoj kev tom qab 出炉. Ntawm lawv, qhov kub thiab txias txiav txim siab txhua yam.
I. Kev faib tawm los ntawm Tempering kub rau hauv Peb Pawg (Core Framework)
| Hom | Qhov kub thiab txias | Organic hloov | Tau txais cov khoom |
Tej kev siv |
| Tsawg-kub tempering | 150 ~ 250 degree | Hloov ntawm martensite mus rau tempered martensite | Hardness tseem tsis hloov pauv (HRC saum toj 55), tshem tawm qee qhov kev ntxhov siab sab hauv | Siv rau cov cuab yeej, ntsuas cov cuab yeej, thiab cov khoom uas yuav tsum tau muaj zog hardness thiab hnav tsis kam |
| Nruab nrab -temperature tempering | 350 ~ 500 degree | → Tempered pearlite | Siab elastic txwv + qee qhov toughness | Siv rau springs, springs, thiab qhov xav tau elasticity |
| High -kub tempering | 500 ~ 650 degree | → Tempered sorbite | Qhov zoo tshaj plaws sib npaug ntawm lub zog thiab toughness (tempered mob) | Siv rau shafts, txuas rods, thiab siab -lub zog seamless kav (N80/P110 hom) |
Rau cov kav dej steel, cov kav dej kub uas koj pom feem ntau yog cov uas ua rau siab -kub tempering: tom qab quenching, temper ntawm 550 ~ 650℃kom tau "siab zog + zoo toughness" sorbite qauv.
II. Cov kauj ruam tshwj xeeb ntawm kev ua haujlwm tempering
1. Temper tam sim ntawd tom qab quenching - lub hauv paus ntsiab lus yog "quench tam sim ntawd thiab npau taws", nws yog qhov zoo tshaj rau hloov mus rau lub qhov cub tempering kom sai li sai tau thaum lub workpiece tsis txias tag kom tsis txhob tawg vim lub sij hawm ntev quenching.
2. Thauj khoom rau hauv lub qhov cub kom cua sov - lub workpiece yog loaded rau hauv lub cub tawg thiab rhuab los yog muab tso rau hauv lub cub tawg ntawm lub hom phiaj kub. Qhov kub thiab txias yog xaiv raws li lub hom phiaj ntawm lub rooj, xws li 550 ~ 620℃rau siab -kub tempering.
3. Tuav (qhov tseem ceeb parameter) - tso cai rau kev hloov pauv ntawm cov qauv kom txaus thiab cov kev ntxhov siab sab hauv yuav tsum tau muab tshem tawm tsis tu ncua.
Cov mis empirical yog:
Rau cov pa roj carbon steel thiab hlau alloy, feem ntau kwv yees li ntawm 1.5 ~ 2.5 feeb / hli ntawm cov thickness zoo;
Kuj feem ntau siv "Ntau dua lossis sib npaug li 2 teev raws li qhov txwv qis" rau kev rwb thaiv tsev;
Alloy steel xav tau kev rwb thaiv tsev ntau dua li cov pa roj carbon steel vim hais tias cov ntsiab lus alloy diffuse maj mam.
4. Unloading thiab cooling - txoj kev txias tom qab tempering muaj qhov cuam tshuam me me. Qhov kev coj ua yog:
Carbon steel: cua txias txaus;
Alloy steel (tshwj xeeb tshaj yog cov uas muaj Cr, Mn, Ni) yuav tsum tau maj mam txias (nyob rau hauv lub cub tawg los yog xuab zeb txias) los tiv thaiv ob hom tempering brittleness.
5. Kev tshuaj xyuas - siv lub hardness tester los tshuaj xyuas seb qhov hardness puas nyob rau hauv lub hom phiaj los txiav txim seb qhov kub ntawm tempering puas tsim nyog (yog tias qhov hardness siab dhau lawm, ua kom lub tempering kub ntxiv rau lwm zaus; yog tias nws qis dhau, txo nws).
III. Peb qhov teeb meem hauv kev ua haujlwm
Pit piav
Zam qhov tempering brittleness tsam Ib feem ntawm cov hlau alloy yuav muaj kev poob qis hauv qhov cuam tshuam ntawm qhov kub ntawm 250-400℃(thawj hom) thiab qeeb txias (hom thib ob) - xaiv qhov txias txias los yog zam qhov chaw no
Lub sij hawm tuav tsis txaus Core tsis siab siab, sab nraud yog mos thiab sab hauv yog tawv, kev ua haujlwm tsis sib xws
Kub sib txawv 20-30℃qhov sib txawv ntawm qhov kub thiab txias tuaj yeem ua rau lub hardness poob ntau HRC, qhov sib txawv ntawm qhov cub kub yog qhov tseem ceeb heev
IV. Xav txog ua ke nrog quenching (tag nrho cov txheej txheem quenching thiab tempering)
Cua sov (Austenitization 800 ~ 950 degree) → Tuav → ceev ceev (dej / roj / PAG) → [Quenching tiav, tau martensite]
→ Tam sim ntawd hloov mus rau lub qhov cub tempering → Tuav ntawm lub hom phiaj kub (xws li 580℃× 2h) → Cua txias / qeeb txias → [Quenching thiab tempering tiav, tau txais sorbite]
→ Hardness/Performance soj ntsuam
Lub mnemonic: quenching txiav txim siab "hardness", tempering txiav txim siab "toughness", xaiv qhov kub thiab txias yog qhov tseeb, lub sij hawm txaus, txias nyob ntawm hom hlau.
