1. Yuav ua li cas quench tab sis tsis nyuaj?
Nws yog feem ntau hnov hauv qhov chaw quenching tias qhov chaw yog quenched yam tsis muaj hardening. Lub hom phiaj ntawm quenching yog los txhim kho qhov hardness ntawm qhov chaw, tsis nyuaj yog tsis hu ua quenching. Nws zoo nkaus li quenched los ntawm sab nraud, tab sis sab hauv tsis quenched. Muaj peb qhov laj thawj rau quenching es tsis yog hardening:
(1) quenching kub (austenitizing kub) tsis txaus los yog lub sij hawm tuav tsis txaus, thiab lub austenitizing tsis tiav;
(2) tus nqi cua txias tsis txaus;
(3) sib tov.
Peb qhov kev ntsuas hauv qab no tuaj yeem siv rau lub hom phiaj no:
(1) Kev txiav txim siab seb qhov kub austenitizing ntawm cov txheej txheem tawv tawv ntawm cov khoom puas txaus,
Nws yog ib qho tsim nyog los txiav txim siab qhov no. Qhov ntsuas kub uas qhia rau ntawm tus pas ntsuas kub lossis cov ntawv sau yog qhov ntsuas kub ntawm qhov kawg ntawm lub thermocouple, tsis yog qhov kub ntawm qhov. Nws yuav tsum tau muab sau tseg tias peb xav tau qhov kub thiab txias ntawm lawv tus kheej.
(2) Xav txog seb qhov txias txias txaus txaus. Txhawm rau kom quench thiab harden steel, nws yuav tsum tau txias ntawm tus nqi siab tshaj qhov tseem ceeb ntawm qhov txias txias. Ntawm lawv, nyob rau hauv lub nroog cheeb tsam tseem ceeb (txog 550 degree) yuav tsum tau txias nrog ib tug ceev ntawm txog 160C / S los yog ntau tshaj. Qhov kub ntawm qhov quench thiab txoj kev sib tov yuav tsum tau kuaj xyuas. Tsis tas li ntawd, qhov chaw muab tso rau hauv lub tank los yog tawb rau batch quenching (paub pawg quenching), thiab ib feem quenching ob qhov txias txias yog txawv, yog li peb yuav tsum tau xyuam xim rau txoj kev ntawm lub cub tawg.
(3) Qhov teeb meem ntawm kev sib tov yog dab tsi? Kev sib xyaw yog qhov txaus ntshai tshaj plaws hauv kev kho cua sov. Yog tias sib tov tshwm sim, qhov kev cia siab quenching tsis tuaj yeem ua tiav. Txoj hauv kev yooj yim tshaj plaws kom paub seb qhov sib tov puas yog siv lub txim taws. Txoj kev kuaj lub txim tuaj yeem tshawb xyuas qhov sib tov raws li cov khoom siv hluav taws xob thiab cov paj qhuav ntawm cov pa roj carbon. Yog li cov neeg ua haujlwm kho cua sov kom paub txog cov qauv no, ua ntej kev kho cua sov yuav tsum ua qhov kev sim ntsuas, mus rau cov khoom ua ntej kuaj.
Siv cov kev ntsuas saum toj no nyob rau tib lub sijhawm, tab sis kuj them nyiaj rau kev kho mob ntawm decarbonization los yog oxidation, qhov txuas ntawm daim tawv nqaij. Yog hais tias lub cub tawg yog carburizing cua, nws yog qhov zoo tshaj kom ntxiv nitrogen.
Txoj kev txhaj tshuaj peening tuaj yeem siv los tshem tawm cov tawv nqaij oxide. Tsis tas li ntawd, thaum cov residual austenite ntau dua, nws tseem yuav ua rau tsis muaj quenching hardness, uas yog qhov zoo tshaj plaws ntawm kev kho mob khaub thuas. Lub hardness yog txhim kho los ntawm kev kho mob txias.
2. Dab tsi ua rau cov pob muag muag?
Lub hardness ntawm qhov chaw tom qab kev kho cua sov (quenching, tempering) feem ntau yog kuaj los ntawm cov qauv. Hauv qhov ntsuas hardness, yog tias tus nqi tsis sib npaug, nws qhia tau tias muaj qhov muag muag. Lub hauv paus ua rau ntawm qhov chaw mos yog qhov tsis sib xws quenching es tsis yog qhov kub tsis sib xws. Nws tsis yog ntau npaum li qhov quenching kub tsis sib npaug, tab sis qhov txias yog feem ntau tsis sib xws. Yog tias cov hlau raug suav hais tias muaj cov thermal conductivity zoo, ces qhov tsis sib xws ntawm cov cua txias ua rau cov chaw mos, qhov kev xav no yog qhov tsim nyog dua. Tau kawg, yog tias qhov tshwm sim ntawm cov decarbonization hauv zos, lossis hauv zos carburizing, txawm tias qhov txias txias tsis sib xws, kuj tseem yuav ua rau quenching soft point, ua rau tsis sib xws. Tsuav nws tsis yog cov khoom tsis sib xws, nws tuaj yeem suav tau tias qhov tsis sib xws yog qhov tshwm sim los ntawm qhov tsis sib xws.
Txawm hais tias qhov kub thiab txias muaj qhov tsis sib xws thiab mos, tab sis ntev li ntev raws li qhov kub thiab txias ntawm cov cua sov ua ke los txiav txim siab, steel tempering kub tsis sib xws yog tsis hnyav heev. Yog li cov pob muag muag feem ntau tshwm sim los ntawm qhov tsis sib xws. Vim tias tempering yuav tsis tshwm sim qhov teeb meem ntawm qhov tsis sib xws, yog li yog tias muaj qhov muag muag, thawj qhov kev txiav txim siab yuav tsum yog qhov phem tshwm sim ntawm qhov tsis sib xws. Nws yog qhov tseeb tias qhov hardness ntawm qhov chaw quenched los ntawm tag nrho yog siab dua li cov txheej txheem hardness, uas yog tshwm sim los ntawm tempering tsis txaus; Ntawm qhov tsis sib xws, yog tias qhov hardness tsawg, nws yog tshwm sim los ntawm tempering ntau dhau. Nyob rau hauv ib lo lus, lub uneven hardness ntawm qhov chaw quenching yog tshwm sim los ntawm uneven quenching. Yog li thawj qhov uas yuav tsum tau them sai sai rau yog lub teeb quenching.
Raws li ib sab ntawv, qhov tseeb ntawm Rockwell hardness tester yuav tsum yog: HRC av 1; Qhov tseeb ntawm Shaw hardness yuav tsum yog Hs 3.
3. Yuav ua li cas tsis txaus annealing thiab softening tshwm sim?
Muaj cov xwm txheej uas tsis yog softening hauv annealing, uas yog qhov tshwm sim ntawm kev tsis zoo annealing. Feem ntau ntawm cov laj thawj rau kev ua tsis zoo yog qhov ua kom txias tsis zoo. . Feem ntau hais lus, hauv paus ntsiab lus, annealing yog ua los ntawm qhov cub txias. Tab sis rau qhov me me, los yog zoo hardenability ntawm steel qhov chaw, nrog rau qhov cub txias yuav poob nthav sai sai thiab ua rau softening me me txaus. Qhov txias txias los ntawm austenization kub txog li 550 degree C yog qhov zoo tshaj plaws hauv kev ua kom mos, thiab nws yog ib qho tseem ceeb uas cov hlau txias txias heev hauv qhov kub thiab txias. Nyob rau hauv cov xwm txheej tshwj xeeb, nws yog qhov zoo tshaj plaws los siv isothermal annealing, uas yog, los ntawm austenitizing kub mus rau 650 ~ 680C qhov kub thiab txias qhov cub rau isothermal processing, yog tias siv isothermal annealing, txawm li cas los zoo hardenability, steel yuav ua tau tag nrho annealed softening. .
4. Dab tsi yog vim li cas rau qhov softening ntawm qhov chaw quenched?
Feem ntau hais lus, qhov tawv tawv ntawm qhov chaw carburized thiab high-frequency quenched qhov chaw yog softer dua li ntawm cov subsurface nyob ze ntawm qhov chaw, feem ntau yog vim cov residual austenite nyob rau hauv lub nto txheej. Muaj residual stress (σr) nyob rau saum npoo ntawm qhov chaw quenched ib feem, yog li qhov saum npoo yuav tsum yog ib qho nyuaj, tab sis nws yog mos vim muaj cov residual austenite.
Kev kho mob khaub thuas ntawm qhov chaw no hardens thiab nce hardness, uas yog pov thawj ntawm residual austenite.
Yog li ntawd, qhov chaw quenched nto yuav tsum hnav tsis kam, feem ntau yuav tsum tau siv cov kev kho mob txias. Lawm, qhov chaw txias yuav tsum tau tempered ntawm qhov ntsuas kub (180 ~ 200 degree).
Yog hais tias koj decarbonize lub nto, ntawm chav kawm, lub hardness ntawm deg yuav txo. Qhov chaw tawv tawv feem ntau yog qhov ua tiav, yog li qhov ua rau ntawm qhov muag muag tsis yog decarbonization ntau li residual austenite. Puas yog qhov ua rau deg softening decarbonization lossis residual austenite? Ntev npaum li kev kho mob khaub thuas yuav nkag siab.
Yog hais tias lub hardness nce tom qab kev kho mob khaub thuas, nws yog lub softening los ntawm residual austenite: yog hais tias lub hardness yog unchanged, nws muaj peev xwm yuav xaus lus tias softening los ntawm decarbonization.
5. Yuav ua li cas xyuas seb nws puas tau tempered ntawm qhov kub thiab txias?
Secondary tempering hardening ntawm kev kub ceev steel (SKH) thiab tuag plhaub hlau (SKOIl). - Feem ntau txais yuav kub tempering (500 ~ 700C). Txawm li cas los xij, nws tsis yooj yim los txiav txim siab seb nws puas yog cov khoom tsis muaj tempering tom qab quenching los yog cov khoom hardened los ntawm theem nrab tempering tsuas yog xyuas cov hardness ntawm cov khoom. Nyob rau hauv cov ntaub ntawv no, ntev li ntev raws li lub tempering ntawm 400 degree: uas yog, los ntawm 400 degree tempering, yog hais tias lub hardening (HRC) tsis hloov, nws yog pov thawj tias cov khoom tau undergone ob tempering (siab kub tempering); Ntawm qhov tsis sib xws, yog tias qhov hardness txo qis, nws tau ua pov thawj tias nws tsis tau tempered los ntawm kev kub siab.
