Hauv kev kho cua sov hlau, quenching thiab tempering yog ob qho tseem ceeb heev thiab feem ntau siv cov txheej txheem uas ua lub luag haujlwm txiav txim siab hauv kev txhim kho cov khoom siv. Txawm li cas los xij, ib lo lus nug uas tau nyiam ntau yam tab sis tseem tsis muaj cov lus teb meej yog: Muaj pes tsawg zaus tuaj yeem quenching thiab tempering tiag tiag rov ua dua? Cov lus teb rau lo lus nug no suav nrog ntau yam, suav nrog cov ntaub ntawv tshawb fawb, cov qauv kev kho cua sov, thiab cov ntawv thov tsim tawm, uas yuav tau tham txog hauv qab no.
1. Basic Principles and Micro-Mechanisms of Quenching and Tempering
Qhov xwm ntawm Quenching thiab Microstructural Transformation
Quenching suav nrog cua sov cov khoom siv hlau rau qhov kub thiab txias (feem ntau saum Ac3 lossis Ac1 qhov tseem ceeb), tuav nws rau ib lub sijhawm kom ua tiav tag nrho lossis ib nrab austenitization, thiab tom qab ntawd txias nws ntawm tus nqi siab tshaj qhov txias txias (feem ntau hauv dej, roj, lossis lwm yam khoom cua txias) kom tau siab -hardness microstructures. Lub ntsiab tseem ceeb ntawm cov txheej txheem no yog txhawm rau txhawm rau diffusion-raws li theem hloov pauv los ntawm kev ua kom txias sai, ua tiav qhov kev hloov pauv tsis hloov pauv- hom kev hloov pauv, yog li tau txais cov qauv metastable martensitic.
Thaum lub sij hawm quenching, cov khoom cua txias nkhaus yuav tsum zam qhov "lub qhov ntswg" ntawm C- nkhaus kom paub meej tias austenite tsis decompose rau hauv pearlite lossis bainite. Kev tsim ntawm martensite yog nrog los ntawm kev nthuav dav ntim (kwv yees li 1-1.5%), uas ua rau muaj kev cuam tshuam loj thiab thermal stresses hauv cov khoom. Kev sib sau ntawm cov kev ntxhov siab sab hauv tuaj yeem tsis tsuas yog ua rau cov khoom deformation tab sis kuj tuaj yeem ua rau tawg, tshwj xeeb tshaj yog nyob rau hauv high-carbon steels thiab cov khoom siv nrog cov duab nyuaj.
Mechanism ntawm Tempering
Tempering yog txheej txheem kev kho cua sov uas cov khoom quenched yog rhuab mus rau qhov kub hauv qab qhov tseem ceeb (A1) (feem ntau 150-650 degree), tuav rau lub sijhawm tsim nyog, thiab tom qab ntawd txias. Cov txheej txheem no ua tiav microstructural stabilization los ntawm atomic diffusion:
- Thaum lub sij hawm qis-kub tempering (100{3}}250 degree), supersaturated carbon nyob rau hauv martensite precipitates li ε-carbide, tsim tempered martensite, thiab kev ntxhov siab nyob rau hauv ib feem yog relieved.
- Thaum lub sij hawm nruab nrab -kub tempering (250-500 degree), khaws cia austenite decomposes, thiab martensite hloov mus rau hauv tempered troostite, ho txhim kho toughness.
- Thaum lub sij hawm siab -kub tempering (500-650 degree), carbides coalesce thiab loj hlob, tsim tempered sorbit, ua rau cov khoom zoo heev txhua yam.
Thaum lub sij hawm tempering txheej txheem, lub nucleation, kev loj hlob, thiab spheroidization ntawm carbides, raws li zoo raws li redistribution ntawm alloying ntsiab, tag nrho cov ho cuam tshuam rau qhov kawg khoom.
2. Cov ntsiab lus tseem ceeb cuam tshuam rau tus naj npawb ntawm qhov ua tau rov ua dua
Evolution of Material Composition thiab Microstructure
Kev kam rau siab ntawm cov ntaub ntawv hlau nrog sib txawv sib xyaw kom rov quenching thiab tempering nws txawv heev. High-cov cuab yeej carbon hlau (xws li T8, T10), vim lawv cov ntsiab lus carbon siab (0.8-1.0%), tsim cov pa roj carbon siab martensite tom qab quenching, uas yog nkig thiab muaj ntau microcracks. Txhua lub voj voog quenching ua rau:
- Rov qab coarsening thiab refinement ntawm austenite nplej.
- Kev puas tsuaj thiab rov- nag lossis daus ntawm carbide.
- Ua kom muaj kev sib cais ntawm cov khoom tsis huv ntawm cov ciam teb nplej.
Cov kev tshawb fawb soj ntsuam pom tau hais tias tom qab 3-4 rov quenching cycles, qhov cuam tshuam toughness ntawm high-carbon steel txo los ntawm 15-20%, thiab tawg rhiab heev.
Nyob rau hauv sib piv, alloy structural steels (xws li 40Cr, 42CrMo) pom zoo tiv thaiv temper softening thiab grain loj hlob vim muaj cov alloying ntsiab xws li Cr, Mo, thiab Ni. Cov ntsiab lus no nce tus naj npawb ntawm qhov ua tau rov qab los ntawm cov txheej txheem hauv qab no:
- Kev tsim cov hlau nplaum ruaj khov carbides uas inhibit grain ciam tsiv teb tsaws.
- Ua kom qhov kub thiab txias recrystallization, ncua cov txheej txheem rov qab.
- Txhim kho cov kev daws teeb meem ntxiv dag zog rau cov teebmeem, tswj xyuas microstructural stability.
Precise Control ntawm kev kho cua sov txheej txheem Parameters
Kev cuam tshuam ntawm quenching tsis nyob ntawm tus naj npawb ntawm repetitions feem ntau yog tshwm sim hauv cov hauv qab no:
Kev Tswj Kub Kub
Kev xaiv ntawm quenching kub ncaj qha cuam tshuam rau austenite grain loj. Nrog txhua lub voj voog quenching, nplej zoo li coarsen. Siv qhov ntsuas kub qis dua (30-50℃saum Ac3) thiab lub sijhawm tuav luv dua tuaj yeem tswj hwm kev loj hlob ntawm cov nplej. Kev tshawb fawb qhia tau hais tias thaum austenite grain loj coarsens los ntawm qib 8 txog qib 5, lub neej qaug zog ntawm cov khoom txo los ntawm kwv yees li 30%.
Kev xaiv qhov txias nruab nrab
Cov yam ntxwv txias ntawm cov xov xwm sib txawv sib txawv heev:
- Dej quenching: ceev ceev txias, tab sis loj kub sib txawv ntawm sab hauv thiab sab nraud ntawm lub workpiece, ua rau muaj kev nyuaj siab heev concentration.
- Roj quenching: Lub zog txias txias, ntau qhov sib txawv ntawm qhov kub thiab txias.
- Martempering: Tuav saum lub martensite pib kub (Ms) kom txo tau kev hloov pauv kev ntxhov siab.
Rau kev kho cua sov rov qab, nws raug nquahu kom siv cov xov xwm nrog qhov txias txias kom tsis txhob muaj cua sov ntau dhau.
Optimization ntawm cov txheej txheem tempering yog qhov tseem ceeb sib npaug:
- Tempering kub yuav tsum ua kom muaj kev ntxhov siab txaus thaum tsis txhob muaj qhov muag muag ntau.
- Lub sijhawm Tempering yuav tsum tso cai rau nag lossis daus txaus thiab spheroidization ntawm carbides.
- Ntau lub voj voog tempering tuaj yeem tshem tawm cov austenite ruaj khov.
Engineering kev txiav txim siab ntawm workpiece loj thiab zoo li
Cov khoom loj loj (xws li pwm, yob) ntsib cov teeb meem tseem ceeb thaum rov quenching:
- Thaum tus ntoo khaub lig-sectional thickness tshaj 100mm, nws nyuaj rau cov tub ntxhais txias tus nqi kom ncav cuag tus nqi tseem ceeb.
- Tom qab ntau qhov kev kho cua sov, cov txheej txheem decarburization saum npoo sib sau ua ke, cuam tshuam rau kev ua haujlwm qaug zog.
- Thermal thiab transformational stresses superimpose, ua deformation tswj nyuaj.
Cov teeb meem kev ntxhov siab ntau tshaj tawm nyob rau hauv complex -zoo li tus workpieces (xws li iav, cov cuab yeej txiav):
- Cov cheeb tsam kev ntxhov siab xws li cov ces kaum ntse thiab grooves yog qhov ua rau tawg tawg.
- Tsis yog- synchronous theem transformation ntawm junctions ntawm nyias thiab tuab seem ua rau complex sab hauv kev nyuaj siab.
- Txhua lub voj voog kho cua sov ua rau deformation, cuam tshuam rau qhov raug.
3. Kev xyaum ua engineering hauv kev siv tswv yim
Kev Tswj Xyuas Kev Tswj Xyuas Zoo thiab Kev Ntsuas Kev Ntsuas
Ib qho kev saib xyuas zoo yuav tsum tau tsim kom muaj thaum rov ua cov txheej txheem kho cua sov:
- Kev ntsuas hardness gradient ua ntej thiab tom qab txhua lub voj voog kho cua sov.
- Ultrasonic flaw detection los xyuas seb puas muaj kab nrib pleb.
- Kev tshuaj ntsuam metallographic los soj ntsuam cov nplej loj thiab kev faib cov carbide.
- Kev ntsuam xyuas kev ntxhov siab seem los ntsuas lub xeev kev ntxhov siab.
Tus nqi -Kev Tshawb Fawb Txog Kev Pabcuam
Kev lag luam ntawm kev kho cua sov rov ua dua yuav tsum muaj kev xav txog:
- Tus nqi ncaj qha: kev siv hluav taws xob, khoom siv qis qis, nqi zog.
- Cov nqi zoo: Cov khoom poob, cov nqi rov ua dua.
- Cov nqi them nqi: Kev xa khoom qeeb los ntawm kev ncua sij hawm ntau lawm.
Cov kev tshawb fawb qhia tau hais tias rau cov khoom siv dav dav, tus naj npawb ntawm kev kho cua sov rov qab feem ntau tsis tshaj 3 zaug; rau siab - tus nqi pwm, raws li kev tswj hwm nruj, nws tuaj yeem ncav cuag 5-7 zaug.
Cov ntawv thov raug
Rov qab kho cua sov ntawm Tuag Steels
Thaum cov txheej softening tshwm rau ntawm H13 kub ua haujlwm tuag hlau thaum lub sijhawm ua haujlwm, nws qhov kev ua tau zoo tuaj yeem rov qab los ntawm kev rov quenching thiab tempering:
1. Ua ntej, ua annealing kom tshem tawm cov kev pabcuam -kev ntxhov siab.
2. Siv lub tshuab nqus tsev quenching ntawm 1030℃nrog kev ua kom txias.
3. Kub ob zaug ntawm 580-600 degree, rau 2 teev txhua zaus.
4. Tus naj npawb ntawm repetitions feem ntau tswj tsis pub dhau 3 zaug.
Reconditioning Treatment of High -Speed Steel Tools
Rau hnav W6Mo5Cr4V2 siab-ceev steel cov cuab yeej:
- Thawj anneal kom txo hardness rau 25-30 HRC.
- Tshav kub siv lub qhov cub ntsev da dej, quench ntawm 1210-1230℃.
- Kub peb zaug ntawm 560 degree, rau 1 teev txhua zaus.
- tuaj yeem rov ua dua 2-3 zaug thaum tswj kev txiav.
4. Advanced Technologies thiab Kev Txhim Kho Yav Tom Ntej
Intelligent Heat Treatment Systems
Cov cuab yeej siv kho cua sov niaj hnub txhim kho kev ruaj ntseg ntawm kev kho dua tshiab los ntawm cov thev naus laus zis hauv qab no:
- Ntau- cheeb tsam kub tswj kom ntseeg tau tias qhov cub kub tsis sib xws.
- Kev saib xyuas online thiab hloov kho cov xov xwm txias.
- Tsis siv neeg kaw thiab taug qab cov txheej txheem tsis ua haujlwm.
- Kev ua kom zoo ntawm cov txheej txheem kho cua sov raws li cov ntaub ntawv loj.
Cov ntaub ntawv tshiab thiab cov txheej txheem
Txoj kev loj hlob ntawm cov ntaub ntawv tshiab muaj peev xwm ua kom muaj cov kev kho cua sov rov qab:
- Ultra-zoo grained steels: High grain ciam ceev inhibits grain loj hlob.
- Nano- nag lossis daus muaj zog steels: Nano-carbides txhim kho tempering stability.
- Cov ntaub ntawv ua haujlwm tau zoo: Cov khoom sib xyaw tsim raws li kev ua tau zoo ntawm cov khoom sib txawv.
Simulation thiab Prediction Technologies
Khoos phis tawj simulation plays lub luag haujlwm tseem ceeb hauv kev kho cua sov dua:
- Temperature field simulation los kwv yees qhov sib xws ntawm cov cua txias.
- Microstructure transformation simulation rau kev kwv yees kev hloov pauv.
- Kev ntsuam xyuas qhov kev ntxhov siab los ntsuas qhov deformation thiab kev pheej hmoo tawg.
- AI-raws li optimization ntawm cov txheej txheem tsis.
