Thaum cov neeg feem coob hnov 'martensitic stainless hlau', lawv tam sim ntawd xav 'nyuaj'. Qhov ntawd tsis yog qhov yuam kev, tab sis nws yog qhov pib ntawm ntau qhov kev nkag siab yuam kev hauv kev yuav khoom thiab kev thov. Zaj dab neeg tiag tiag tsis yog hais txog kev ua tiav Rockwell C tus lej siab xwb; Nws yog hais txog kev seev cev sib txawv ntawm chemistry, kev kho cua sov, thiab kev lag luam uas tsis tuaj yeem zam. Kuv tau pom ntau qhov chaw nres tsheb vim tias ib tus neeg tau teev cov generic 410 lossis 420 rau 'kev tiv thaiv corrosion thiab lub zog' yam tsis muaj kev nkag siab dab tsi uas muaj nyob hauv khw hauv pem teb. Lub quenching tawg, qhov seem ntawm warping tom qab hardening, xav tsis thoob tsis muaj toughness nyob rau hauv dab tsi zoo li ib tug robust tivthaiv - cov no yog cov lus qhia tiag tiag. Qhov no tsis yog cov ntaub ntawv kawm; nws yog yam koj kawm tom qab scrapping ob peb pawg.
Tus Cwj Pwm Tseem Ceeb thiab Nws Qhov Kev Pom Zoo
Cia peb muab nws rov qab. Martensitic stainless hlau Nws yog ib qho tseem ceeb ntawm hardenable Fe-Cr-C alloy. Tus yuam sij yog qhov hloov pauv martensitic - nrawm nrawm los ntawm qhov kub thiab txias uas cuam tshuam cov pa roj carbon atoms, tsim kom muaj qhov tsis sib xws, supersaturated lub cev-centered tetragonal qauv. Qhov ntawd yog lub hauv paus ntawm hardness. Tab sis ntawm no yog thawj qhov ua tau zoo: qhov siab dua cov pa roj carbon rau hardness (xws li hauv 440C), qhov ntau koj cuam tshuam weldability thiab, me ntsis counterintuitively rau 'stainless' hlau, corrosion kuj. Chromium xav tau kev sib txuas nrog cov pa roj carbon monoxide los tsim cov carbide, uas yuav siv nws tawm ntawm kev daws, txo cov chromium dawb uas muaj los ua cov txheej txheem oxide passive. Yog li, tej zaum koj yuav muaj qhov zoo nkauj zoo nkauj 58 HRC hniav uas tseem pom cov pob zeb xeb.
Nyob rau hauv peb machining ua hauj lwm ntawm Qingdao Qiangsenyuan Technology Co., Ltd. (QSY), peb nquag ntsib no dual. Tus neeg siv khoom yuav xa daim duab kos rau lub valve los yog lub twj tso kua mis hauv 17-4PH (cov nag lossis daus-hardening martensitic hom, tab sis cia peb pab pawg ntawm no rau kev sib tham). Lawv xav tau cov khoom sib nqus, lub zog tawm los, thiab qee qhov kev tiv thaiv corrosion. Qhov kev sib tw pib ntawm cov khoom siv raw. Lub bar Tshuag qhov kev ntxhov siab los ntawm nws tus kheej cov txheej txheem tsim khoom tuaj yeem ua rau muaj kev puas tsuaj rau peb lub sijhawm tom ntej CNC machining. Peb tau kawm ib txwm qhia kom meej cov khoom lag luam txo kev ntxhov siab rau qhov tseem ceeb, lossis peev nyiaj rau kev kho cua sov nruab nrab ntawm peb tus kheej. Nws yog tus nqi, tab sis nws yog pheej yig dua ib feem warping 0.1 hli tom qab kho cua sov kawg.
Kev kho cua sov nws tus kheej yog qhov chaw kos duab raws li kev tshawb fawb. Nws tsis yog 'set thiab tsis nco qab' qhov kev pab cuam cub tawg. Qhov kub austenitizing yog qhov tseem ceeb - qis dhau, thiab koj tsis tau txais kev daws tag nrho; siab dhau lawm, koj yuav muaj feem ntau khaws cia austenite lossis grain loj hlob. Tom qab ntawd lub quench: roj yog tus qauv, tab sis qhov agitation thiab kub ntawm cov roj quenchant teeb meem loj heev rau kev txo qis distortion thiab cracking txaus ntshai, tshwj xeeb tshaj yog nyob rau hauv complex peev castings nrog txawv cross-sections. Peb ib zaug muaj ib pawg ntawm nyias-walled peev casting prototypes nyob rau hauv 410 tawg yuav luag audibly thaum quench. Zaj lus qhia? Rau cov duab sib txawv, qee zaum qib martensitic tsis yog cov lus teb, lossis cov qauv tsim xav tau radii thiab cov tuab tuab peb tuaj yeem sib cav rau hauv DFM (Design for Manufacture) theem.
Machining thiab Finishing: Lub Khw Pem Teb Qhov Tseeb
Machining annealed martensitic stainless hlau yog ib tug tsiaj nyaum txawv ntawm machining nws daim ntawv hardened. Hauv lub xeev annealed (feem ntau ua rau ib ncig ntawm 85 HRB), nws yog gummy. Nws tsis tawg chips huv si zoo li 303 austenitic; nws nyhav rau daim ntawv ntev, stringy chips uas muaj peev xwm welding rau lub cuab tam thiab puas nto tiav. Cov cuab yeej geometry, txheej txheej (TiAlN ua haujlwm zoo), thiab cov cua txias siab kom tawg thiab tshem tawm cov chips yog tsis sib tham. Peb khiav cov haujlwm no ntawm peb qhov hnyav dua, nruj CNC machining chaw rau dampen vibration.
Kev kho cua sov tom qab kev kho cua sov yog qhov tsis muaj rov qab los. Thaum koj harden nws, ib qho ntxiv machining yog qhov nyuaj heev, txwv qhov tseem ceeb rau kev sib tsoo lossis EDM. Cov kab ke no yog qhov tseem ceeb. Peb muaj kev mob siab rau kev kawm ntau xyoo dhau los nrog cov khoom siv iav. Tus neeg siv xav tau cov hniav txiav tom qab hardening kom paub meej geometry zoo meej. Peb yuav tsum tau txais daim ntawv cog lus rau tus kws tshaj lij nrog CBN sib tsoo lub log, thiab tus nqi thiab lub sijhawm dhau mus yog qhov tseem ceeb. Tam sim no, peb cov qauv kev coj ua, thiab qhov peb qhia cov neeg siv khoom ntawm peb lub platform tsi.com, yog rau tshuab mus rau qhov kawg qhov ntev hauv lub xeev annealed, accounting rau kev kwv yees kev loj hlob / shrinkage los ntawm hardening thiab tempering voj voog. Qhov no yuav tsum muaj lub tsev qiv ntawv sib sib zog nqus ntawm cov ntaub ntawv keeb kwm txog seb cov geometries tshwj xeeb hauv cov qib tshwj xeeb txav, uas peb tau tsim dua 30 xyoo hauv casting thiab machining.
Kev ua tiav yog lwm qhov nuance. Ib tug passivated martensitic stainless hlau ib feem yuav tsis muaj corrosion kuj ntawm 316L ib feem. Cov txheej txheem passivation (feem ntau yog nitric lossis citric acid) pab, tab sis nws tau txhim kho cov txheej txheem tsis muaj zog. Rau cov ntawv thov nyob rau hauv ib puag ncig corrosive me me, zoo li qee yam khoom siv ua khoom noj lossis cov khoom siv hauv hiav txwv, cov khoom siv hluav taws xob zoo tom qab passivation tuaj yeem ua qhov sib txawv. Nws smoothes micro-peaks, txo qhov chaw rau pitting pib. Nws yog ib kauj ruam ntxiv, tab sis nws txuas qhov sib txawv ntawm cov khoom siv txwv thiab cov ntawv thov.
Kev Xaiv Khoom: Thaum Yuav Siv Nws, Thaum Yuav Taug Kev
Qhov no yog lub hauv paus ntawm kev txiav txim siab tshaj lij. Martensitic stainless hlau ci qhov chaw uas koj xav tau kev sib xyaw ua ke ntawm nruab nrab corrosion kuj, siab zog / hardness, thiab feem ntau, sib nqus permeability. Xav tias turbine hniav nyob rau hauv tej qhov chaw ib puag ncig, cutlery, riam hniav, cov cuab yeej phais, bearing haiv neeg nyob rau hauv tsis-submerged daim ntaub ntawv, thiab fasteners zoo li high-strength bolts. Cov nag lossis daus-tawv tawv sib txawv xws li 17-4PH yog qhov zoo heev rau cov khoom siv dav hlau, muaj zog aerospace uas yuav tsum tuav nruj nruj tom qab kev kho mob qis-distortion.
Txawm li cas los xij, koj yuav tsum nquag zam nws rau kev tsim cov welded tag nrho (tshwj tsis yog cov txheej txheem kho mob ua ntej / tom qab cua sov), rau cov ntawv thov hauv thaj chaw uas muaj chloride nplua nuj (xws li nyob ze dej hiav txwv tsis muaj kev tiv thaiv), lossis qhov cuam tshuam ntawm qhov kub thiab txias yog qhov tseem ceeb. Lub cev-centered qauv ntawm martensite muaj ductile-rau-brittle hloov kub; nws tuaj yeem ua rau muaj kev phom sij hauv kev pabcuam txias. Kuv nco qab qhov kev soj ntsuam tsis ua hauj lwm rau qhov tawg ntawm hydraulic piston pas nrig siv nyob rau hauv lub tshuab ua liaj ua teb sab nraum zoov thaum lub caij ntuj no; 420 cov khoom tau ntsib cov hardness spec tab sis tawg ntawm kev cuam tshuam. Austenitic stainless hlau los yog cov hlau tsis kub kub yuav yog qhov tseeb.
Ua haujlwm nrog tshwj xeeb alloys xws li cobalt-based lossis npib tsib xee-raws li alloys qee zaum muab cov tshuaj zoo nkauj dua, txawm tias tus nqi siab dua. Piv txwv li, rau ib qho hnyav hnyav thiab me ntsis corrosive slurry twj impeller, hardened martensitic stainless zoo li 440C tej zaum yuav raug txiav txim siab, tab sis ib tug Stellite (cobalt alloy) weld-overlay los yog ib qho khoom. peev casting nyob rau hauv ib tug npib tsib xee alloy zoo li Alloy 255 yuav muab superior life-cycle nqi txawm tias tus nqi siab dua. Ntawm QSY, peb feem ntau muaj cov kev sib tham no, coj cov neeg siv khoom los ntawm qhov kev ua tau zoo, kev tsim khoom, thiab tag nrho cov nqi.
Case nyob rau hauv Point: A Valve Component Saga
Ib qho piv txwv ntawm peb lub khw. Ib tug neeg xav tau kev cai siab-siab valve qia. Cov spec hu kom zoo corrosion kuj mus rau ib tug me me tshuaj, siab hnav tsis kam ntawm sealing nto, thiab tsis muaj deformation mus tas li nyob rau hauv 900 MPa tensile stress. Lawv pib npaj 316L rau corrosion kuj. Peb thawb rov qab. 316L tsis tuaj yeem ua kom tawv txaus rau kev hnav. Peb npaj siab 440C rau qhov hnav khaub ncaws tab sis ntsib qhov sib txawv ntawm corrosion.
Qhov kev daws teeb meem yog ib txoj hauv kev hybrid. Lub cev qia lub ntsiab yog machined los ntawm 17-4PH nyob rau hauv tus mob A (annealed), ces hnub nyoog mus rau H900 tom qab machining, muab nws lub zog tseem ceeb. Qhov tseem ceeb sealing thaj av ntawd yog nyob rau hauv lub zos nto-hardened siv ib tug laser txheej txheem los tsim ib tug hardened martensitic cheeb tsam yam tsis muaj kev cuam tshuam rau tej khoom cov khoom corrosion. Nws yog tus txheej txheem uas tsis yog tus qauv uas yuav tsum muaj kev sib koom tes zoo ntawm peb tshuab pab neeg thiab tus khub kho cua sov. Ib feem ua tiav, tab sis qhov kev tshem tawm yog qhov ntshiab martensitic stainless hlau tsis yog lo lus teb solo; nws yog ib feem ntawm cov khoom siv lub tswv yim.
Qhov kev daws teeb meem zoo li no yog qhov uas cov ntaub ntawv cov ntaub ntawv dav dav poob qis. Lawv muab koj lub zog thiab cov nqi corrosion nyob rau hauv lub chaw kuaj acid, tab sis lawv tsis qhia koj yuav ua li cas cov khoom coj cwj pwm thaum koj tab tom sim tuav ib tug 0.02mm kam rau ua rau nyias flange uas yuav pom 800 ° C quench. Qhov kev paub ntawd yog los ntawm kev ua, ua tsis tau qee zaus, thiab rov ua dua. Nws yog vim li cas cov tuam txhab uas muaj keeb kwm ntev hauv casting thiab machining, zoo li peb nrog ntau tshaj peb xyoo lawm, sau ib hom kev paub tacit uas muaj txiaj ntsig zoo li cov tshuab hauv pem teb.
Xaus Kev xav: hwm tus txheej txheem
Yog li, lo lus kawg yog dab tsi martensitic stainless hlau? Nws yog ib tsev neeg muaj zog, ntau yam khoom siv, tab sis nws xav tau kev hwm. Nws tsis yog 'poob-hauv' hloov rau carbon steel thaum koj xav tau me ntsis ntxiv corrosion kuj. Nws tus cwj pwm yog qhov tseem ceeb khi rau nws cov keeb kwm thermal. Qhia meej tias nws ua tiav yuav tsum xav txog tag nrho cov kev tsim khoom lag luam - los ntawm cov xwm txheej zeb ntawm cov khoom lag luam lossis cov qauv tsim. plhaub molding, los ntawm txhua qhov machining op, ncaj nraim rau hauv qhov cub kho cua sov thiab mus rau lub rooj zaum zaum kawg tshuaj xyuas.
Qhov yuam kev loj tshaj plaws yog kho nws raws li cov khoom lag luam. Nws yog cov khoom siv ua haujlwm siab uas xav tau cov txheej txheem kev ua tau zoo. Thaum koj tau txais nws txoj cai, cov txiaj ntsig tau tshwj xeeb: cov khoom uas tawv, ruaj khov, thiab haum rau lub hom phiaj. Thaum koj tau txais nws tsis ncaj ncees lawm, qhov ua tsis tiav yog kim thiab qhia. Lub hom phiaj yog kom leverage tus qub thiab txo qhov tom kawg, uas nyob rau hauv qhov kawg, yog lub ntsiab ntawm cov tswv yim engineering nrog txhua yam ntaub ntawv, tshwj xeeb tshaj yog ib tug xav tau thiab nqi zog raws li martensitic stainless.
