Casting yog ib qho tseem ceeb hauv kev lag luam hauv lub teb chaws kev lag luam, tab sis kev tswj, tsim thiab txheej txheem ntws ntawm cov txheej txheem casting feem ntau cia siab rau kev txiav txim siab, yog li qhov zoo ntawm castings yog ib qho nyuaj rau lav thiab cov khoom seem yog siab. Siab casting yog hom tshwj xeeb casting. Nws cov ntsiab lus yog ib txoj hauv kev uas cov kua los yog ib nrab ua kua hlau ua rau cov pwm kab noj hniav ntawm kev kub ceev nyob rau hauv kev kub siab thiab solidifies nyob rau hauv siab kom tau castings. Txhawm rau kom tau txais cov khoom zoo, qib siab-casting qhov chaw thiab xyuas kom meej tias qhov chaw tuag-casting ua tau raws li qhov yuav tsum tau ua ntawm smoothness, meej qauv, ntom qauv, thiab lub zog siab, nws yog ib qho tsim nyog yuav tsum tau sib koom ua ke thiab sib koom ua ke ntawm cov kev cuam tshuam hauv txoj kev tuag-casting. Rau aluminium alloy tuag-casting qhov chaw, los ntawm kev npaj ntau lawm mus rau ntau lawm, muaj ntau yam kev sib txuas thiab ntau yam cuam tshuam, nrog rau cov ntaub ntawv, pwm, khoom siv, txheej txheem, thiab lwm yam.
Porosity defects nyob rau hauv tuag castings thiab lawv ua
Cov workpieces ua los ntawm txhuas alloy tuag-casting feem ntau yog scrapped vim muaj cov pores. Muaj ntau qhov laj thawj rau qhov pores. Thaum daws qhov teeb meem zoo ntawm cov khoom no, feem ntau nyuaj pib. Yuav ua li cas sai thiab raug ntsuas los txo qhov seem ntawm qhov pores? Qhov no yog Cov Teeb Meem uas tag nrho cov aluminium alloy tuag-casting manufacturers muaj kev txhawj xeeb txog.
Nyob rau hauv aluminium alloy tuag-casting ntau lawm, qhov ua rau ntawm pores feem ntau poob rau hauv pawg hauv qab no.
Porosity tshwm sim los ntawm qhov tsis zoo refining degassing zoo
Nyob rau hauv txhuas alloy tuag-casting ntau lawm, lub pouring kub ntawm molten txhuas kua yog feem ntau ntawm 61 0 thiab 66 0 degree . Ntawm qhov kub no, cov pa roj ntau ntau (tsuas yog hydrogen) yaj hauv cov kua txhuas. Lub solubility ntawm hydrogen nyob rau hauv aluminium alloy yog ze ze rau ntawm aluminium alloy. Qhov kub thiab txias yog ze ze. Nyob rau hauv cov kua txhuas ntawm li 660 degree, nws yog hais txog 0.69cm3/100g, thaum nyob rau hauv cov khoom txhuas alloy ntawm txog 660 degree, nws tsuas yog 0.036cm3/100g. Lub sijhawm no, cov ntsiab lus hydrogen hauv cov kua txhuas yog li 0.69cm3 / 100g. 19 rau 20x. Yog li ntawd, thaum aluminium alloy solidifies, ib tug loj npaum li cas ntawm hydrogen raug tso tawm nyob rau hauv daim ntawv ntawm npuas nyob rau hauv lub aluminium alloy tuag casting.
Txo cov roj cov ntsiab lus hauv cov kua txhuas thiab tiv thaiv kom tsis txhob muaj roj ntau los ntawm precipitating thiab ua rau lub qhov hws thaum lub aluminium alloy solidifies. Qhov no yog lub hom phiaj ntawm refining thiab degassing thaum lub sij hawm txhuas alloy smelting txheej txheem. Yog hais tias cov roj cov ntsiab lus nyob rau hauv cov kua txhuas yog Ameslikas txo, cov roj evolved thaum lub sij hawm solidification yuav raug txo, thiab cov npuas generated kuj yuav txo tau. Yog li ntawd, kev kho kom zoo ntawm aluminium alloy yog txheej txheem tseem ceeb heev. Yog hais tias qhov zoo ntawm refining zoo, yuav tsum muaj tsawg pores. Yog hais tias qhov zoo ntawm refining tsis zoo, yuav tsum muaj ntau qhov pores. Kev ntsuas los xyuas kom meej qhov zoo ntawm refining yog xaiv ib tug zoo refining tus neeg sawv cev. Ib tug zoo refining tus neeg sawv cev tuaj yeem tshwm sim los ua npuas ntawm ib ncig ntawm 660 degree. Cov npuas generated tsis yog nruj heev, tab sis yog generated uniformly thiab tsis tu ncua. Los ntawm lub cev adsorption, cov npuas no sib xyaw nrog tus neeg ua haujlwm refining. Cov kua txhuas yog nyob rau hauv tag nrho kev sib cuag, adsorbing hydrogen nyob rau hauv cov kua txhuas thiab coj nws tawm ntawm cov kua nto. Yog li ntawd, lub sij hawm bubbling yuav tsum tsis txhob luv heev, feem ntau 6 mus rau 8 feeb.
Thaum cov aluminium alloy txias rau 300 degree, solubility ntawm hydrogen hauv aluminium alloy tsuas yog tsawg dua 0.001cm3/100g, uas tsuas yog 1/700 ntawm cov kua hauv lub xeev. Cov pores uas ua los ntawm nag lossis daus ntawm hydrogen tom qab solidification yog dispersed thiab me me. Cov pinholes tsis cuam tshuam rau huab cua to thiab qhov chaw machined, thiab yog qhov yooj yim pom ntawm qhov muag liab qab.
Thaum cov kua txhuas solidifies, cov npuas uas tsim los ntawm nag lossis daus ntawm hydrogen kuj loj, feem ntau nyob rau hauv nruab nrab ntawm qhov kawg solidification ntawm txhuas kua. Txawm hais tias lawv kuj tau tawg, cov npuas no feem ntau ua rau cov dej xau, thiab hauv cov xwm txheej hnyav, cov khoom ua haujlwm feem ntau raug khawb.
Pores tshwm sim los ntawm kev tso pa tawm tsis zoo
Nyob rau hauv aluminium alloy tuag-casting, vim qhov tsis zoo tso channel ntawm cov pwm thiab cov qauv tsim qauv tsis zoo ntawm cov pwm, cov roj hauv cov kab noj hniav tsis tuaj yeem ua kom tiav thiab ua haujlwm zoo thaum lub sij hawm tuag-casting, uas ua rau muaj qhov pores hauv qee yam. tsau qhov chaw ntawm cov khoom. Cov pores tsim los ntawm cov roj hauv cov pwm kab noj hniav yog qee zaum loj thiab qee zaum me. Cov phab ntsa sab hauv ntawm qhov pores muaj cov xim oxidation tshwm sim los ntawm oxidation ntawm txhuas thiab cua. Lawv txawv ntawm qhov pores uas tsim los ntawm hydrogen gas nag lossis daus. Cov phab ntsa sab hauv ntawm hydrogen gas nag lossis daus pores tsis zoo li lub qhov cua thiab tsis muaj oxidation xim. Nws yog ib lub ci grey sab hauv phab ntsa. Rau cov pores uas tshwm sim los ntawm cov pa tawm tsis zoo, cov pa tawm ntawm cov pwm yuav tsum tau txhim kho, thiab cov tawv nqaij uas seem nyob rau ntawm cov pa tawm ntawm cov pwm tuaj yeem zam lub sijhawm.
Porosity tshwm sim los ntawm huab cua nkag los ntawm qhov tsis zoo tuag-casting tsis
Hauv kev tsim cov tuag-casting, cov txheej txheem tuag-casting raug xaiv tsis raug. Lub filling ceev ntawm txhuas hydraulic casting yog ceev heev, yog li ntawd cov roj nyob rau hauv cov kab noj hniav tsis tuaj yeem ua tiav thiab smoothly extruded los ntawm kab noj hniav nyob rau hauv lub sij hawm, thiab yog kos rau hauv cov kua txhuas los ntawm cov kua txhuas. Vim yog qhov saum npoo ntawm aluminium alloy, Tom qab txias ceev, nws yog qhwv rau hauv ib tug solidified aluminium alloy plhaub thiab tsis tuaj yeem tawm, tsim cov pores loj. Hom pores no feem ntau nyob hauv qab ntawm lub workpiece. Qhov nkag ntawm cov kua txhuas yog tsawg dua qhov kawg confluence, pear-puab lossis oval-puab, thiab muaj ntau thiab loj ntawm qhov kawg solidification point. Rau hom pore no, lub filling ceev yuav tsum tau hloov kho kom ntseeg tau tias aluminium alloy kua ntws mus zoo dua yam tsis muaj kev ua haujlwm siab ceev thiab huab cua nkag.
Shrinkage qhov ntawm aluminium alloy
Aluminium alloys, zoo li lwm yam ntaub ntawv, shrinkage thaum solidification. Qhov siab dua qhov ntsuas kub ntawm aluminium alloy, qhov ntau dua qhov shrinkage. Ib qho pore tshwm sim los ntawm qhov ntim shrinkage tshwm sim nyob rau hauv qhov kawg solidification ib feem ntawm cov hlau, uas yog irregular nyob rau hauv cov duab thiab loj. Qee zaum hauv ib lub mesh zoo li. Feem ntau nyob rau hauv cov khoom, nws coexists nrog pores vim hydrogen evolution thaum lub sij hawm solidification. Muaj shrinkage pores nyob ib ncig ntawm lub hydrogen evolution pores los yog curling pores, thiab muaj filamentous los yog mesh-zoo li pores extending rau sab nraum ib ncig ntawm cov npuas.
Rau hom pores no, peb yuav tsum pib nrog qhov kub thiab txias los daws nws. Yog tias cov txheej txheem tuag-casting tau tso cai, cov txhuas ua kua ua kua kub thaum lub sij hawm tuag-casting yuav tsum raug txo kom ntau li ntau tau. Qhov no tuaj yeem txo qhov ntim shrinkage ntawm casting, txo qhov shrinkage thiab shrinkage porosity. Yog hais tias xws li pores feem ntau tshwm nyob rau hauv lub cua sov qhov chaw, koj muaj peev xwm txiav txim siab ntxiv core rub los yog txias hlau los hloov qhov kawg solidification ib feem thiab daws tau qhov teeb meem ntawm to.
Porosity tshwm sim los ntawm ntau phab ntsa thickness sib txawv ntawm cov khoom
Cov khoom zoo li feem ntau raug kev txom nyem los ntawm qhov teeb meem ntawm cov phab ntsa tuab tuab heev. Qhov nruab nrab ntawm phab ntsa thickness yog qhov twg cov kua txhuas thaum kawg solidifies, thiab nws kuj yog qhov feem ntau yuav tsim pores. Cov pores ntawm phab ntsa tuab no yog sib xyaw ntawm nag lossis daus pores thiab shrinkage pores, uas tsis zoo li qub. kev ntsuas uas tuaj yeem tiv thaiv tau.
Thaum tsim cov qauv ntawm cov khoom, kev txiav txim siab yuav tsum tau muab rau txo qis qhov teeb meem ntawm qhov tsis sib xws lossis ntau dhau ntawm phab ntsa tuab, siv cov qauv hollow, thiab ntxiv cov tub ntxhais rub lossis hlau txias, lossis dej txias, lossis ua kom txias ntawm no hauv pwm yuav tsum tau txiav txim siab. hauv kev tsim pwm. ceev. Hauv kev tuag-casting ntau lawm, yuav tsum tau them nyiaj mloog mus rau qhov nyiaj ntawm subcooling nyob rau hauv cov cheeb tsam nrog loj thickness, thiab lub pouring kub yuav tsum tau txo kom tsim nyog.
Los ntawm kev faib tawm saum toj no ntawm qhov pores, nws tuaj yeem pom tias muaj ntau qhov laj thawj vim li cas cov khoom tsim cov pores hauv aluminium alloy tuag-casting ntau lawm. Nws yog ib qho tsim nyog yuav tsum paub qhov ua rau thiab sau cov tshuaj kom raug los daws qhov teeb meem. Cov kev ntsuas tseem ceeb thiab txoj hauv kev los tiv thaiv qhov pores yog:
- Txhawm rau kom ua kom zoo dua thiab degassing zoo ntawm aluminium alloy smelting, siv cov tshuaj zoo refining thiab degassing cov neeg ua haujlwm kom txo cov roj cov ntsiab lus hauv cov kua txhuas, thiab tshem tawm cov oxides tam sim ntawd xws li scum thiab npuas ntawm cov kua dej kom tsis txhob muaj roj nkag mus ntxiv. nyob rau hauv tuag castings.
- Xaiv tus neeg sawv cev tso tawm zoo. Tus neeg sawv cev raug xaiv yuav tsum tsis txhob tsim cov roj thaum lub sij hawm tuag casting thiab muaj kev tso tawm zoo.
- Xyuas kom meej tias cov pa tawm ntawm cov pwm yog du thiab tsis thaiv, thiab cov pa tawm hauv pwm yog tawm tag nrho. Tshwj xeeb tshaj yog nyob rau ntawm qhov kawg polymerization point ntawm cov kua txhuas, cov pa tawm channel yuav tsum tsis muaj kev cuam tshuam.
- Kho qhov kev tuag-casting tsis, thiab pwm filling ceev yuav tsum tsis txhob ceev dhau los tiv thaiv huab cua nkag. Qhov kub ntawm casting kuj yuav tsum tau tswj.
- Hauv cov khoom tsim thiab pwm tsim, yuav tsum tau them nyiaj mloog mus rau kev siv cov tub ntxhais rub thiab txias kom txo cov phab ntsa thickness sib txawv.
- Rau qhov pores uas feem ntau tshwm nyob rau hauv qhov chaw ruaj khov, cov pwm thiab tsim yuav tsum tau txhim kho.
Kev tsim kho tshiab hauv aluminium alloy tuag-casting tshuab
Nyob rau hauv xyoo tas los no, tib neeg tau txuas ntxiv txhim kho lub tshuab nqus tsev txhawm rau txhawm rau daws cov teeb meem ntawm qhov pores thiab shrinkage kab noj hniav hauv cov tuag castings kom lawv tuaj yeem tsim cov tuag castings nrog lub zog siab, siab ceev, weldability, kho cua sov, twistability thiab lwm yam khoom. Ntxiv nrog rau kev tuag casting, cov thev naus laus zis tshiab xws li nyem casting thiab semi-khoom tuag casting tau tsim, thiab feem ntau hu ua "high-density die casting method".
Lub tshuab nqus tsev tuag casting tshuab
Lub tshuab nqus tsev tuag-casting txoj kev tshem tawm los yog ib nrab tshem tawm cov roj hauv cov pwm kab noj hniav kom txo tau cov cua siab hauv pwm kab noj hniav kom yooj yim pwm filling thiab tshem tawm cov roj hauv cov hlau yaj, kom cov hlau yaj ua rau cov pwm kab noj hniav nyob rau hauv siab, thiab nyob rau hauv siab solidified kom tau dense tuag castings.
Oxygenated tuag-casting tshuab
Feem ntau ntawm cov gases nyob rau hauv tuag castings yog N2 thiab H2, uas yuav luag tsis muaj O2. Lub ntsiab yog vim li cas O 2 reacts nrog active hlau los tsim cov khoom oxides, uas muab lub hauv paus theoretical rau oxygenated tuag casting tshuab. Oxygenated tuag casting yog sau cov pwm kab noj hniav nrog oxygen los hloov cov huab cua ua ntej tuag casting. Thaum nkag mus rau hauv lub pwm kab noj hniav, ib feem ntawm cov pa tawm tawm ntawm qhov tso pa tawm, thiab cov pa oxygen ntxiv ua haujlwm nrog cov hlau molten los tsim cov oxide dispersed, tsim lub tshuab nqus tsev hauv pwm, yog li tau txais cov pore-dawb tuag casting.
Semi-solid die-casting technology
Semi-khoom tuag casting yog ib qho cuab yeej uas ua rau cov hlau ua kua thaum nws khov, tau txais cov slurry nrog cov khoom sib xyaw ntawm li 50% lossis ntau dua ntawm qhov txias txias, thiab tom qab ntawd ua cov slurry los ntawm kev tuag casting. Tam sim no, muaj ob txoj hauv kev rau semi-khoom tuag casting txheej txheem: ntws txoj kev thiab thixoforming txheej txheem. Lub qub yog pub cov kua hlau rau hauv ib lub thoob tsim tshwj xeeb txhaj tshuaj molding, qhov twg shear yog siv los ntawm ib tug kauv ntaus ntawv kom txias nws mus rau hauv ib tug semi-khoom slurry, thiab ces tuag casting yog ua. Cov tom kawg yog pub cov khoom hlau los yog cov chips rau hauv lub tshuab txhaj tshuaj molding tshuab, thiab cov khoom siv hlau semi-tiav yog tuag-casted nyob rau hauv cov xwm txheej ntawm cua sov thiab shearing.
Extrusion tuag casting tshuab
Extrusion tuag casting tseem hu ua "kua hlau molding". Nws cov castings muaj qhov ntom ntom zoo, cov khoom siv zoo, thiab tsis muaj pias cov ris tsho. Qee lub lag luam hauv peb lub teb chaws tau siv nws hauv kev tsim khoom tiag tiag. Squeeze die-casting tshuab muaj cov txheej txheem zoo heev. Nws tuaj yeem tsis tsuas yog hloov cov tsoos tuag-casting, nyem casting, low-pressure casting, thiab lub tshuab nqus tsev tuag-casting txheej txheem, tab sis kuj yog sib xws nrog sib txawv siab casting, nruam casting thiab nruam forging, thiab semi-solid rheological casting txheej txheem. . Cov kws tshaj lij ntseeg tias extrusion tuag-casting thev naus laus zis yog kev siv thev naus laus zis tshiab uas nthuav dav ntau yam txheej txheem, muaj txiaj ntsig zoo, muaj tswv yim tshiab, thiab nyuaj heev.
Electromagnetic twj tso kua mis low-pressure casting technology
Electromagnetic twj tso kua mis low-pressure casting yog ib qho tshiab uas tsis tshua muaj siab casting txheej txheem. Piv nrog cov roj-based low-pressure casting technology, nws yog qhov sib txawv kiag li ntawm cov txheej txheem kev ua haujlwm siab. Nws siv lub zog hluav taws xob tsis sib cuag los ua ncaj qha rau cov kua hlau, uas txo cov oxidation thiab nqus cov teeb meem tshwm sim los ntawm impure compressed cua thiab siab ib nrab, thiab ua tiav kev thauj mus los du thiab ntim cov kua txhuas. Tiv thaiv cov pa phem thib ob uas tshwm sim los ntawm kev kub ntxhov. Tsis tas li ntawd, lub twj tso kua mis electromagnetic yog tswj los ntawm lub computer cov ntsiab lus, thiab cov txheej txheem ua tiav yog qhov tseeb thiab rov ua dua. Cov txheej txheem no muaj cov txiaj ntsig zoo ntawm cov txiaj ntsig, cov khoom siv kho tshuab, qhov zoo thiab kev siv hlau. Raws li kev tshawb fawb txuas ntxiv mus tob zuj zus, cov tshuab no tau dhau los ua neeg paub tab.
Xaus
Vim yog qhov tsis sib xws ntawm phab ntsa ntawm aluminium alloy disc thiab cylindrical tuag-casting qhov chaw, tuag-casting zoo tsis xws luag xws li pores thiab shrinkage qhov yuav tshwm sim. Los ntawm kev sim ua ntu zus, cov kws ua choj tuaj yeem nrhiav kev ua kom zoo dua cov txheej txheem tuag-casting. Nyob rau hauv txoj kev no, cov txheej txheem tsim nyog yuav raug xaiv, thiab qhov tseeb casting nqi pov tseg tuaj yeem zam, nqa cov txiaj ntsig tseem ceeb rau kev lag luam. Nws cia siab tias lub ncauj lus no tuaj yeem yog qee qhov kev pab rau kev tsim khoom tiag tiag. Lub hom phiaj kawg yog tsim cov khoom tsim nyog tuag-casting kom tau raws li qhov xav tau tiag tiag ntawm kev lag luam. Judging los ntawm domestic thiab txawv teb chaws tuag-casting kev tshawb fawb nyob rau hauv lub xyoo tsis ntev los no, nrog rau qhov tob ntawm theoretical kev tshawb fawb, tshwj xeeb tshaj yog cov kev loj hlob ntawm lub computer simulation technology, ntws qauv ntawm cov hlau filling kab noj hniav, lub solidification txheej txheem ntawm hlau nyob rau hauv kab noj hniav, thiab muaj. tau zoo theoretical breakthroughs nyob rau hauv lub ndlwg siab ntawm lub internal hlau kua, qhov kub gradient ntawm pwm, thiab deformation ntawm pwm.