1.Vim li cas ho tsis tuaj yeem vuam ncaj qha?
Melting Point tsis sib haum
Galvanized Steel: Lub melting point ntawm hlau yog kwv yees li ~ 1500 degree, thaum lub melting point ntawm zinc txheej nyob rau saum npoo yog kwv yees li ~ 420 degree, thiab lub boiling point yog kwv yees li ~ 907 degree.
Aluminium Alloy: Melting point yog kwv yees li ~ 660 degree.
Problem: When the heat input is sufficient to melt the steel (>1500 degree), aluminium alloy yuav tau melted, evaporated, los yog hlawv los ntawm. Txawm li cas los xij, thaum lub ntsuas kub tswj tau nyob rau hauv qhov kev siv tau rau aluminium alloys (kwv yees li 660 degree), cov hlau nyob deb ntawm kev ncav cuag lub xeev molten.
Teeb meem Alumina
A dense alumina film with an extremely high melting point (~2050℃) instantly forms on the surface of the aluminum alloy. Cov yeeb yaj kiab no cuam tshuam qhov ntws thiab kev sib txuas ntawm cov hlau molten thiab yuav tsum tau muab tshem tawm ua ntej vuam (feem ntau yog los ntawm AC TIG lossis mechanical scraping), tab sis cov txheej txheem yog complex.
Zinc Volatilization thiab porosity
Ua ntej ncav cuag lub melting kub ntawm cov hlau, zinc txheej (qhov kub ntawm 907 degree) boils thiab volatilizes, ua ib tug loj npaum li cas ntawm zinc vapor. Cov zinc vapors no tau kos rau hauv lub pas dej molten, tsim ntau lub qhov hws tom qab weld solidifies, ua rau cov weld tsis muaj zog thiab lub zog.
Nyob rau tib lub sij hawm, cov zinc volatilized kis kab mob rau vuam teeb thiab tungsten electrode, ua rau cov tshuaj lom dawb zinc oxide fumes uas ua rau muaj kev phom sij tseem ceeb rau cov neeg ua haujlwm.
2.Dab tsi yog cov kauj ruam cuam tshuam nrog kev sib txuas ntawm cov tshuab?
Riveting: Kev sib txuas yog tsim los ntawm kev siv qhov muag tsis pom kev rivets lossis khoom rivets. Cov txheej txheem yog yooj yim, tsawg- nqi, thiab haum rau automated ntau lawm.
Bolted Connections: Tshem tau, haum rau cov qauv xav tau kev saib xyuas lossis hloov kho.
Kev ceev faj: Electrochemical corrosion (Gavaniz corrosion) yuav tsum tau txiav txim siab. Hlau (raws li cathode) thiab txhuas (raws li anode) tsim ib tug galvanic cell nyob rau hauv lub xub ntiag ntawm ib tug electrolyte (xws li huab cua ntub), ua rau kom ceev corrosion ntawm aluminium alloy. Txoj kev daws teeb meem yog siv cov khoom siv insulating, cov nplhaib roj hmab, los yog cov sealant kom cais cov chaw sib cuag.
3.Dab tsi yog qhov zoo thiab qhov tsis zoo ntawm kev siv cov nplaum nplaum?
Qhov zoo:
Zam kom tsis txhob muaj cua sov- thaj chaw cuam tshuam thiab teeb meem intermetallic compound.
Lawm cais ob hlau, tiv thaiv electrochemical corrosion.
Muab zoo sealing thiab vibration damping zog.
Disadvantages: Yuav tsum tau lub sij hawm ntev curing, xav tau kev huv saum npoo av, thiab tsis yooj yim disassembled.
4.Dab tsi yog kev ceev faj rau cov txheej txheem vuam tshwj xeeb?
Kev sib txhuam txhuam vuam: Qhov no yog ib qho khoom siv- lub xeev koom nrog cov txheej txheem uas siv lub siab- nrawm rotating nplawm lub taub hau kom tsim kom muaj cua sov los ntawm kev sib txhuam, softening cov ntaub ntawv tsis melting lawv, thiab ces khi lawv ua ke los ntawm stirring. Nws zoo suppresses tsim ntawm intermetallic tebchaw, tab sis cov cuab yeej yog kim thiab muaj cov yuav tsum tau hais txog lub workpiece zoo thiab kev siv tau.
Explosion welding: Cov txheej txheem no siv lub siab loj uas tsim los ntawm kev tawg mus rau qhov chaw ntawm ob lub hlau. Nws yog tsuas yog siv rau kev tsim cov nplooj ntawv sib xyaw, tsis yog rau ntawm - chaw koom.
Bragging:
Bragging aluminium: Siv aluminium-raws li cov khoom siv hlau (melting point ~ 500-600 degree), lub tshav kub tsis txaus rau yaj hlau, tab sis ib daim ntawv cog lus tuaj yeem ua tiav los ntawm adhesion ntawm cov hlau muab tub lim thiab txhuas, thiab nruab nrab ntawm cov hlau muab tub lim thiab zinc txheej. Txoj kev no ua rau cov zinc plating puas thiab tsis muaj zog.
Bragging steel (xws li, nrog zinc-raws li cov hlau): Cov cua sov yuav yaj cov aluminium alloy, ua rau nws tsis haum.
5.Nyob rau hauv kev siv ntau lawm, dab tsi yuav tsum tau ua ntej raws li cov khoom yuav tsum tau ua tau zoo, ntau lawm lub sij hawm, thiab tus nqi?
Riveting + Sealant (Kev lag luam thiab txiaj ntsig)
Tus kheej - tho riveting (Suitable rau ntau- txheej boards)
Adhesive bonding (Rau qhov xav tau siab ntawm kev zoo nkauj thiab sealing)
Glue-riveting composite (Rau qhov xav tau ntawm lub zog thiab kev ntseeg siab heev)