Thaum koj hnov '420 stainless hlau', thawj yam uas tej zaum yuav los rau hauv siab yog ' riam'. Thiab koj tsis yog yuam kev, tab sis qhov ntawd kuj yog qhov uas qhov kev sib tw pib. Nyob rau hauv lub foundry thiab machining ntiaj teb no, kho 420 tsuas yog ib tug 'qib cutlery' yog ib tug ceev txoj kev khiav mus rau hauv cov teeb meem. Nws yog martensitic stainless, uas txhais tau tias nws yog hardenable, tab sis tus yam ntxwv heev yog rab ntaj ob-edged. Kuv tau pom ntau qhov haujlwm uas qhov spec hu rau 420 tsuas yog vim nws yog lub npe paub, tsis muaj kev nkag siab tiag tiag ntawm nws tus cwj pwm thaum thiab tom qab ua tiav. Qhov sib txawv ntawm nws cov theoretical zog thiab qhov muaj tiag ntawm kev hloov pauv lub casting lossis ib qho khoom lag luam rau hauv ib qho tiav yog qhov ua haujlwm tiag tiag - thiab cov lus qhia nthuav dav - tshwm sim.
Lub Hardenability Reality thiab Machining Headaches
Cia peb tham txog lub hauv paus ntawm 420: nws 12-14% chromium cov ntsiab lus nrog cov pa roj carbon txaus (nyob ib ncig ntawm 0.15% min) kom tso cai rau hardening. Ntawm daim ntawv, koj sov kho nws thiab tau txais kev hnav zoo thiab lub zog. Hauv kev xyaum, tshwj xeeb tshaj yog nyob rau hauv peev casting uas kuv lub tuam txhab, QINGDAO QIANGSENYUAN TECHNOLOGY CO., LTD., specializes nyob rau hauv, as-cast qauv yog ib qho tseem ceeb. Yog tias koj tsis tswj hwm txoj cai txias los ntawm lub ncuav, koj tuaj yeem tau txais cov khoom khaws cia ntau austenite lossis tsis sib xws carbide tsim. Qhov ntawd ua rau tsis sib haum xeeb tom qab, txawm tias koj lub voj voog kho cua sov tom ntej zoo li cas. Peb kawm qhov no thaum ntxov nrog ib pawg ntawm cov khoom siv valve. Cov spec hu rau HRC 48-52 tom qab hardening thiab tempering. Peb tau txais txhua yam los ntawm 44 txog 55 hla tib pawg. Tus neeg ua txhaum? Me me, yuav luag negligible variations nyob rau hauv lub phab ntsa thickness ntawm cov castings uas hloov lub solidification tus nqi. Cov ntaub ntawv tsis ceeb toom koj txog qhov ntawd.
Tom qab ntawd los ntawm machining. Pre-hardened 420 yog abrasive. Nws nyiam ua haujlwm hnyav. Koj xav tias koj tab tom noj kev txiav zoo, thiab mam li nco dheev koj lub cuab yeej kub hnyiab vim tias cov khoom tsuas yog nyuaj dua hauv qab txiav ntug. Peb ua ntau yam CNC machining hauv tsev ntawm peb qhov chaw (koj tuaj yeem pom qee yam ntawm peb lub peev xwm ntawm https://www.tsingtaocnc.com), thiab 420 xav tau kev hwm. Cov cuab yeej geometry, txheej, thiab pub tus nqi tsis yog qhov kev coj ua zoo tshaj plaws ntawm no; lawv yog qhov sib txawv ntawm txoj haujlwm tau txais txiaj ntsig thiab khawb tag nrho cov khoom kim heev castings. Kev xaiv coolant thiab ntws los ua ib qho kev hais lus tseem ceeb ntawm lub khw hauv pem teb. Nws tsis yog 'teeb thiab tsis nco qab' cov khoom zoo li qee cov hlau me me.
Kuv nco qab txog ib qhov project rau kev ua zaub mov. Cov neeg siv xav tau lub ntug kom tuav lub ntse tiav ntev. Peb tau hais txog 420, tab sis lawv muaj peev nyiaj nruj thiab xav tau tsawg kawg ntawm kev ua haujlwm tom qab casting. Peb sim xa cov castings kom ze rau cov duab zoo li ua tau kom txo tau tus nqi machining. Kev txav tsis zoo. Qhov me me thiab qhov decarb decarb los ntawm cov txheej txheem casting txhais tau tias thawj qhov kev ua haujlwm tsis sib haum, ua rau muaj kev sib cav thiab tsis zoo ntawm ntug. Peb tau mus ntxiv ib qho kev ntxhib los mos machining thiab ntxuav cov kauj ruam ua ntej qhov kawg grind, uas tau noj cov nyiaj tau los tab sis xa tawm. Zaj Lus Qhia: nrog 420, qee zaum koj tsis tuaj yeem hla cov kauj ruam kom txuag tau nqi. Cov khoom yuav ua rau koj them rau nws tom qab.
Corrosion Resistance: Lub Stainless Misconception
Qhov no yog ib tug loj. Cov neeg pom 'stainless' thiab xav tias nws zoo li 304 lossis 316. Nws tsis yog. 420 muaj ntau dua corrosion kuj. Cov chromium muaj feem ntau rau hardenability, tsis yog rau tsim ib tug robust passive txheej. Nyob rau hauv ib qho chaw me me corrosive, zoo li qhov chaw ntub dej lossis qee zaus kev sib cuag nrog dej, nws zoo. Tab sis muab tso rau hauv kev sib cuag nrog chlorides los yog acids, thiab nws yuav pom thiab pit. Peb muaj ib tug neeg nyob rau hauv marine kev lag luam uas xav tau 420 rau ib tug me me, high-lub zog fastener. Lawv tau hloov ib feem ntawm carbon steel uas xeb sai heev. Qhov 420 tau siv sijhawm ntev dua, tab sis tsis pub dhau ib xyoos, nws pom qhov pitting. Rau lawv daim ntawv thov, 17-4 PH lossis txawm tias 316 nrog cov tawv tawv kom zoo yuav zoo dua, tab sis tus nqi ua ntej ntshai lawv. Peb tau kawm kom muaj qhov kev sib tham corrosion ua ntej, txhua lub sijhawm, txawm tias nws txhais tau tias thawb rov qab rau qhov kev xaiv thawj zaug.
Lub corrosion kuj tseem hnyav heev nyob ntawm qhov chaw tiav. Lub polished zoo kawg nkaus 420 nto yuav ua tau zoo dua li lub tshuab ntxhib los yog ua-cam khwb cia. Qhov no txuas ncaj qha rau peb plhaub molding thiab peev casting txheej txheem. Nrog peev casting, peb tuaj yeem ua tiav qhov zoo heev tiav ncaj nraim ntawm pwm, uas muab qhov pib zoo dua. Nrog lub plhaub molding, feem ntau yuav tsum tau ntxuav ntau dua. Yog li qhov kev xaiv ntawm cov txheej txheem casting nws tus kheej tuaj yeem cuam tshuam qhov kawg ntawm qhov kev ua tau zoo hauv qhov chaw corrosive, ib yam dab tsi uas tsis pom tseeb thaum koj tsuas yog saib ntawm cov khoom siv lub rooj.
Tom qab-weld los yog tom qab-kub-kho-kho, qhov corrosion kuj yuav siv sij hawm lwm hit yog tias koj tsis zoo pickle thiab passivate. Peb tsis yog xa tawm cov khoom siv hluav taws xob uas tsis muaj cov kauj ruam no. Nws yog ib qho khoom lag luam tus nqi ntxiv, tab sis hla nws txhais tau hais tias ib feem yuav xeb hauv kev thauj mus los lossis kev cia khoom, uas zoo li tsis muaj txiaj ntsig zoo. Nws yog cov txheej txheem me me, tsis zoo nkauj uas txhais tau tias zoo thaum ua haujlwm nrog qib zoo li 420.
Ua haujlwm nrog Alloy Variations thiab Sourcing
420 tsis yog ib yam xwb. Muaj 420, 420F (nrog ntxiv sulfur rau machinability), thiab 420J2 variants nrog cov pa roj carbon sib txawv me ntsis. 420F yog npau suav rau tshuab piv rau tus qauv 420, tab sis nws cov weldability tsis zoo thiab cov sulfide suav nrog tuaj yeem yog cov ntsiab lus tsis muaj zog rau qaug zog lossis xeb. Koj yuav tsum phim qhov variant rau qhov ua haujlwm. Rau ib tug complex, nyias-walled casting uas yuav xav tau nws kim heev CNC machining, peb tuaj yeem thawb rau 420F nrog tus neeg siv khoom pom zoo, nthuav dav kev lag luam tawm. Rau ib feem xav tau kev cuam tshuam zoo, peb yuav ua kom meej ntawm qib 'F'.
Kev muab cov khoom siv zoo ib yam yog lwm qhov kev kos duab me me. Tshaj li 30 xyoo hauv kev lag luam no, peb tau tsim kev sib raug zoo nrog mills thiab distributors peb ntseeg. Qhov sib txawv ntawm qhov huv huv thiab qhov qias neeg rau 420 yog qhov loj rau castability thiab kawg kev ncaj ncees. Cov impurities tuaj yeem ua rau kub tearing thaum lub sij hawm solidification los yog non-metallic inclusions uas dhau los ua cov ntsiab lus tsis ua hauj lwm. Thaum peb tau txais cov khoom siv rau kev khiav lag luam, peb tsis yog yuav '420 stainless hlau'; peb tab tom qhia txog kev xyaum yaj thiab thov cov ntawv pov thawj zeb uas peb tau tshuaj xyuas. Nws yog ib theem ntawm kev mob siab uas cais ib feem uas ua haujlwm los ntawm ib qho uas ua tsis tiav hauv thaj chaw.
Qhov kev tsom mus rau kev ncaj ncees ntawm cov khoom siv yog qhov tseem ceeb rau kev ua li cas QINGDAO QIANGSENYUAN TECHNOLOGY CO., LTD. ua haujlwm. Seb nws yog 420, lwm yam stainless hlau qib, los yog cov nickel-raws li alloys peb kuj tuav, lub tswv yim zoo ib yam: to taub cov khoom ntawm tus ntsuj plig, tsis yog nws cov lej xwb. Koj tuaj yeem pom ntau ntxiv txog peb txoj hauv kev rau cov ntaub ntawv ntawm peb lub xaib, tsi.com. Nws yog lub hauv paus no uas tso cai rau peb los daws cov haujlwm nyuaj nrog qee qhov kev ntseeg siab.
Thaum Xaiv 420 (Thiab Thaum Yuav Taug Kev)
Yog li, tom qab tag nrho cov mob taub hau no, vim li cas siv 420 txhua? Vim tias thaum nws haum, nws yog ib qho kev daws teeb meem zoo. Nws yog qhov zoo heev rau cov khoom uas xav tau kev sib xyaw ua ke ntawm qhov nruab nrab corrosion tsis kam thiab siab hardness / lub zog qhov twg tus nqi them rau qib zoo li 440C lossis 17-4 PH tsis raug cai. Xav txog cov twj tso kua mis, lub valve trim, cov cuab yeej phais (qhov twg nws tuaj yeem polished mus rau qib siab), thiab yog, qee yam riam thiab cov hniav uas yuav tsis pom qhov hnyav hnyav. Nws cov cuab yeej sib nqus kuj yog qhov yuav tsum tau muaj hauv qee qhov kev siv.
Qhov kev txiav txim siab matrix rau peb feem ntau mus zoo li no: Puas yog qhov yuav tsum tau nyuaj? (Yog). Nws puas yuav pom tsuas yog me ntsis corrosion los yog nyob rau hauv ib puag ncig tiv thaiv? (Yog). Puas yog lub geometry haum rau kev tswj cov cua sov kom tsis txhob cuam tshuam? (Qhov tseem ceeb). Puas yog pob nyiaj rhiab? (Ntau zaus). Yog tias feem ntau cov thawv raug txheeb xyuas, 420 yog qhov sib tw muaj zog. Tom qab ntawd peb muaj kev sib tham txog kev tsim qauv casting (ib ntu ntu, dav dav radii), machining lub tswv yim, thiab kev kho cua sov specs ua ntej peb hais. Qhov no tiv thaiv kev xav tsis thoob.
Kuv tau taug kev deb ntawm txoj haujlwm uas qhia txog 420 rau cov khoom siv hauv qab dej los yog qhov chaw rau cov tshuaj tua kab mob. Nws tsis yog ib qho kev khav theeb; nws yog hais txog kev paub txog cov khoom txwv. Thawb cov khoom siv rau hauv daim ntawv thov nws tsis haum rau kev hu rov qab, kev puas tsuaj rau lub koob npe nrov, thiab cov neeg siv khoom tsis zoo siab. Qee zaum, qhov kev pabcuam tshaj lij tshaj plaws uas koj tuaj yeem muab tau yog hais tias, Qhov no tsis yog cov khoom siv zoo, thiab ntawm no yog vim li cas.
The Heat Treatment Dance
Koj tsis tuaj yeem tham txog 420 yam tsis tau dhia tob rau hauv kev kho cua sov. Nws yog cov kauj ruam ua-lossis-break. Austenitizing kub, quench nruab nrab (roj yog tus qauv), thiab lub voj voog tempering tsis yog cov zaub mov uas koj rub los ntawm phau ntawv. Lawv pib cov ntsiab lus. Qhov tseeb tsis hloov raws li qhov loj, ntu tuab, thiab txawm tias yav dhau los machining keeb kwm. Piv txwv li, ib feem nrog hnyav machining stresses xav tau ib tug kev nyuaj siab nyem ua ntej harden thiab temper, los yog nws muaj peev xwm warp dramatically.
Peb ua peb qhov kev kho cua sov hauv tsev rau cov haujlwm tseem ceeb vim peb xav tau kev tswj xyuas ntawd. Rau ib pawg ntawm high-precision scraper hniav, peb pom tias ob chav temper - ib yam dab tsi tsis yog ib txwm hu rau - ua kom muaj kev ruaj ntseg zoo. Thawj qhov npau taws tom qab quenching relieves cov kev ntxhov siab loj, tab sis ib tug thib ob, me ntsis siab dua temper zoo li txawm tawm lub hardness thiab txo ntau ntawm cov residual stresses los ntawm quench nws tus kheej. Qhov tshwm sim yog tsawg zog thaum lub sij hawm kawg micro-sib tsoo. Nws yog cov nuances uas koj khaws ntau pua ntawm cov khoom siv.
Kev saib xyuas yog qhov tseem ceeb. Peb taug qab qhov kub ntawm qhov cub nrog cov sensors ywj siab, tsis yog tus tswj kev nyeem ntawv xwb. Quench roj kub thiab agitation yog tswj. Nws suab yooj yim, tab sis kuv tau pom cov khw muag khoom uas lub tank quench nyob rau hauv lub ces kaum thiab cov roj kub hloov nrog lub caij. Koj yuav tsis tau txais txiaj ntsig zoo nrog 420 li ntawd. Qhov sib txawv ntawm ib qho zoo meej, nkig thiab ib qho warped, tawg yog feem ntau tsuas yog 50 degrees ntawm lub quench los yog 15 feeb ntev heev nyob rau hauv lub austenitizing cub.
Thaum kawg, 420 stainless hlau yog ib qho cuab yeej. Ib qho tshwj xeeb heev. Nws xav tau tus kws kho mob qhov kev nkag siab-kev hwm rau nws qhov kev xav, kev paub txog nws cov kev txwv, thiab cov txheej txheem ceev faj kom qhib nws lub peev xwm. Nws tsis yog cov khoom siv rau cov xws li los yog rushed. Tab sis thaum koj tau txais nws txoj cai, thaum lub casting yog suab, lub machining yog huv si, thiab lub tshav kub kho qhov chaw, nws muab ib tug robust, haumxeeb ib feem uas ua raws nraim li xav tau. Qhov ntawd yog qhov txaus siab uas ua rau koj nyob rau hauv qhov kev ua si, xam cov seev cev ntawm cov hlau, txheej txheem, thiab daim ntawv thov, ib pawg ntawm ib lub sijhawm.
