Silicon hlau (kev lag luam silicon)yog ib tug tseem ceeb additive nyob rau hauv aluminium alloy ntau lawm. Nws cov ntsiab lus tseem ceeb yog Si Ntau dua lossis sib npaug li 98% (cov qib tseem ceeb xws li441#thiab3303#), nrog nruj tswj cov ntsiab lus impurity (Fe Tsawg dua lossis sib npaug rau 0.4%, Al Tsawg dua lossis sib npaug rau 0.4%, thiab lwm yam). Nws compatibility nrog txhuas stems los ntawm ob lub ntsiab yam ntxwv:
Silicon thiab txhuas tuaj yeem tsim ib qho kev daws teeb meem tsis kawg. Ntawm eutectic kub ntawm 577 degree, qhov siab tshaj plaws solubility ntawm silicon nyob rau hauv txhuas mus txog 1.65%, muab chav txaus rau kev tswj kev ua haujlwm.
Qhov sib ntxiv ntawm silicon tuaj yeem txo qhov melting point ntawm aluminium alloys (ntshiab aluminium melts ntawm 660 degree, thaum aluminium alloys muaj 12% silicon yaj ntawm 577 degree), thaum tib lub sij hawm optimizing melt flowability thiab daws cov kev sib tw ntawm complex aluminium cov ntaub ntawv.
Plaub Lub Luag Haujlwm ntawm Silicon hlau hauv Aluminium Ntau Lawm
(1) Kev Txhim Kho Kev Ua Haujlwm: Txhim kho "Mechanical Skeleton" ntawm Aluminium
Silicon hlau ho txhim khu cov tub ntxhais mechanical zog ntawm txhuas alloys los ntawm ib tug dual mechanism ntawm cov khoom siv ntxiv dag zog thiab nag los nag ntxiv dag zog:
Solid Solution Strengthening:
Silicon atoms koom ua ke rau hauv aluminium matrix lattice, inducing lattice distortion, inhibiting dislocation txav, thiab ib txhij txhim kho lub hardness thiab tensile lub zog ntawm aluminium alloy.
Precipitation Strengthening:
Hauv Al-Mg-Si alloys, silicon thiab magnesium tsim Mg₂Si ntxiv zog theem ('theem) ntawm atomic ratio ntawm 1.73: 1. Tom qab T6 kev laus kev kho mob, lub "theem precipitates uniformly, nce lub zog ntawm cov hlau los ntawm 100MPa mus rau ntau tshaj 300MPa.
Synergistic Optimization:
Silicon, ua ke nrog cov ntsiab lus xws li manganese thiab titanium, tuaj yeem tsim AlFeMn dispersed theem (loj 0.5-2μm), inhibiting grain loj hlob thiab ua rau muaj kev cuam tshuam toughness ntawm aluminium alloy los ntawm 20% -30%, zam kev pheej hmoo ntawm brittle puas.
(2) Txhim kho Machining: Txo qhov "Forming nyuaj" ntawm ntau lawm
Hlau silicon yog qhov tseem ceeb los daws qhov mob cov ntsiab lus ntawm aluminium alloy machining, tshwj xeeb tshaj yog tsim rau kev tsim cov txheej txheem nyuaj thiab castings:
Txhim kho Casting Fluidity:
Silicon tuaj yeem txo cov viscosity ntawm aluminium alloy melts los ntawm 30% -40%, ua kom muaj peev xwm ua tau zoo, ua rau nws tsim nyog rau cov txheej txheem nyuaj xws li kev sib xyaw tsheb tuag casting thiab aerospace Cheebtsam.
Txo Kub Cracking Tendency:
Silicon tuaj yeem ua kom zoo dua cov qauv ntawm aluminium alloys, nqaim qhov sib txawv ntawm qhov kub thiab txias, thiab tso cai rau cov kev ntxhov siab tsis sib xws thaum lub sij hawm ua kom txias, txo qhov tshwm sim ntawm kub tawg los ntawm ntau tshaj 60%;
Optimized Machining Kev Ua Haujlwm:
Cam khwb cia txhuas alloys uas muaj 5% -13% silicon tsis tshua muaj rau cov cuab yeej sticking thaum txiav, nce machining efficiency los ntawm 25% -30% thiab txo cov cuab yeej hnav los ntawm 40%, ua rau lawv tshwj xeeb tshaj yog haum rau zus tau tej cov machined qhov chaw.
(3) Txhim kho Durability: Muab Aluminium "Corrosion thiab Wear Resistance Shield"
Silicon hlau tuaj yeem txhim kho cov tshuaj lom neeg ruaj khov thiab hnav tsis kam ntawm aluminium alloys, txuas ntxiv lawv lub neej kev pab cuam:
Txhim kho Corrosion Resistance:
Silicon tuaj yeem tsim cov oxide zaj duab xis ntom ntom (SiO₂-Al₂O₃ zaj duab xis sib xyaw) rau saum npoo ntawm txhuas, cuam tshuam cov tshuaj tiv thaiv ntawm oxygen thiab cov matrix sab hauv, txo cov corrosion ntawm aluminium alloys nyob rau hauv cov av noo, acidic, thiab alkaline ib puag ncig los ntawm 50% -70%, ua rau nws tsim nyog rau marine engineering, sab nraum zoov cov ntaub ntawv.
Txhim kho hnav tsis kam:
Silicon particles nyob rau hauv aluminium alloys muaj siab hardness (Mohs hardness 7.0), uas muaj peev xwm tsim ib tug "hard particle dispersion" qauv, txo kev sib txhuam hnav. Nrog rau cov ntsiab lus ntawm silicon ntawm 3%, aluminium alloy muaj kev sib txhuam coefficient tsawg li 0.052 thiab hnav tus nqi tsuas yog 64.8 mg, ua rau pom kev hnav tsis kam.
Thermal stability optimization:
AA7075 aerospace aluminium alloy uas muaj 0.1-0.2% silicon khaws 85-90% ntawm nws lub zog tom qab 1000 teev ntawm kev raug mob ntawm 150 degree, nrog txo qis kev cuam tshuam rau grain ciam corrosion.
(4) Hloov tau rau ntau qhov xwm txheej: Txhawb nqa "Cross-Kev thov ciam teb" ntawm cov khoom siv txhuas
Cov muaj pes tsawg leeg ntawm cov xim hlau silicon tuaj yeem tswj tau qhov tseeb, ua kom cov txhuas alloys hloov mus rau cov kev xav tau ntawm cov kev lag luam sib txawv, uas yog cov kev txhawb nqa tseem ceeb rau cov nroj tsuag aluminium kom nthuav lawv cov kev lag luam:
Aerospace:
Siv 3303# siab- purity silicon hlau (Si Ntau dua lossis sib npaug li 99.3%, Fe Tsawg dua lossis sib npaug li 0.3%), tswj cov ntsiab lus silicon hauv aluminium alloys mus rau 0.10-0.20%, thiab koom tes nrog Fe / Si piv tswj (1.5-2.0), lub zog ntawm 1.2 × 1. rau 3.7 × 10⁶ cycles, ua tau raws li qhov yuav tsum tau nruj ntawm aircraft tis spars thiab foob pob ua ntxaij propellant tso tsheb hlau luam;
Automotive Manufacturing:
Siv 441# nws yog xim hlau silicon, tswj cov ntsiab lus ntawm silicon ntawm txhuas alloys mus rau 6-10%, ua cua sov-dawb integrated tuag-cam khwb cia qhov chaw, xyuas kom meej tensile lub zog ntau dua los yog sib npaug zos rau 300MPa, thiab txo cov nqi ntau lawm, haum rau lub zog tshiab tsheb lub cev, log hubs, thiab lwm yam khoom;
Kev tsim kho thiab Electronics:
Cov khoom siv hauv tsev zoo tib yam aluminium siv553 # silicon hlau(Si Ntau dua lossis sib npaug li 98%), nrog cov ntsiab lus silicon ntawm 0.5-1.5%, sib npaug zog thiab kev ua haujlwm; aluminium alloys siv rau cov khoom siv hluav taws xob hauv tsev tswj cov ntsiab lus silicon kom tsawg dua lossis sib npaug li 0.2% kom ntseeg tau tias qhov chaw tiav thiab kev ua haujlwm.
Cov ntsiab lus tseem ceeb rau kev tswj cov txheej txheem thaum siv hlau silicon hauv cov nroj tsuag aluminium
(1) Precise tswj cov nyiaj ntxiv
Aluminium alloy qhov rooj:Silicon cov ntsiab lus feem ntau yog 5% -13%; recycled aluminium alloys, vim yog cov ntsiab lus ntawm silicon nyob rau hauv khib nyiab aluminium, tuaj yeem muaj lawv qhov sib ntxiv txo mus rau 5-7%;
Aluminium alloy qhov rooj:Silicon cov ntsiab lus feem ntau yog qis dua 0.5%, ncaj qha ntxiv los ntawm txhuas-silicon intermediate alloys;
Tsis txhob muab ntau dhau:Thaum cov ntsiab lus silicon ntau tshaj 13%, qhov elongation ntawm aluminium alloy yuav txo qis (tsawg dua los yog sib npaug li 5%), toughness yuav deteriorate, thiab nws yuav ua rau brittleness.
(2) Smelting thiab Purification txheej txheem
Smelting kub:Tswj ntawm 720-780℃los xyuas kom meej qhov ua tiav ntawm cov hlau silicon thiab zam kev ua haujlwm tsis zoo tshwm sim los ntawm cov khoom tsis raug;
Kev Kho Mob Purification:Peb -theem ceramic filtration (30 → 50 → 70ppi) + electromagnetic stirring (magnetic field zog 0.15T) yog siv los tshem tawm cov silicon inclusions, txo qhov kev suav loj ntawm 15μm mus rau hauv qab 3μm;
Homogeneous kev kho mob:Ib ob -theem cua sov txheej txheem (300℃/4h + 450℃/12h) yog siv los xyuas kom meej silicon faib thiab txo cov kev hloov pauv.
Core Selection Logic rau Silicon hlau hauv Aluminium Cog
| Aluminium Application Scenarios | Pom zoo Silicon Qib | Silicon Content Requirements | Core Zoo |
| Aerospace- qib aluminium | 3303# | Si Ntau dua lossis sib npaug li 99.3% | High purity, tsis tshua muaj impurities, kev ua haujlwm ruaj khov |
| Automotive tuag castings | 441# | Si Ntau dua lossis sib npaug li 98.0% | Kev ua haujlwm sib npaug, zoo fluidity |
| Standard tsev profiles | 553# | Si Ntau dua lossis sib npaug li 98.0% | Controllable nqi, zoo heev processability |
| Cov khoom siv aluminium rau cov khoom siv hluav taws xob | 2202# | Si Ntau dua lossis sib npaug li 99.5% | Ob peb kab impurities, zoo heev conductivity |
