Brazing ntawm Beryllium-Copper Alloys

Beryllium tooj liab muaj kev tiv thaiv corrosion siab, hluav taws xob conductivity thiab thermal conductivity, ntxiv rau siab zog thiab tsis kam mus rau qhov kub thiab txias.Tsis-sparking thiab non-magnetic, nws yog ib qho tseem ceeb nyob rau hauv mining thiab petrochemical industries.Nrog kev ua haujlwm siab rau kev qaug zog, beryllium tooj liab kuj yog siv rau cov springs, connectors thiab lwm yam uas yuav raug rau cyclical loading.

Brazing beryllium tooj liab yog tus pheej yig thiab ua tau yooj yim yam tsis muaj zog ntawm cov hlau.Beryllium-tooj ​​liab alloys muaj nyob rau hauv ob chav kawm: high-strength C17000, C17200 thiab C17300;thiab high-conductivity C17410, C17450, C17500 thiab C17510.Kev kho cua sov ntxiv ntxiv dag zog rau cov hlau no.

metallurgy

Brazing kub rau beryllium-tooj ​​liab alloys feem ntau yog siab dua lub hnub nyoog-hardening kub thiab kwv yees li tib yam li cov tshuaj-annealing kub.

Cov kauj ruam dav dav rau kev kho cua sov beryllium-tooj ​​liab alloys ua raws li:

Ua ntej, lub alloy yuav tsum tau tov annealed.Qhov no yog ua tiav los ntawm dissolving lub alloy mus rau hauv ib qho kev daws teeb meem yog li nws yuav muaj nyob rau lub hnub nyoog-hardening kauj ruam.Tom qab cov tshuaj annealing, cov hlau yog ceev ceev kom txias rau hauv chav tsev kub los ntawm dej quenching los yog siv cua yuam cua rau nyias qhov chaw.

Cov kauj ruam tom ntej yog lub hnub nyoog hardening, uas yog sub-microscopic, nyuaj, beryllium-nplua nuj hais yog tsim nyob rau hauv cov hlau matrix.Kev laus lub sij hawm thiab qhov kub thiab txias txiav txim qhov nyiaj thiab kev faib tawm ntawm cov khoom no hauv matrix.Qhov tshwm sim yog nce lub zog ntawm alloy.

Alloy Classes

1. High-strength beryllium tooj liab - Beryllium tooj liab yog ib txwm yuav nyob rau hauv cov tshuaj-annealed mob.Qhov no anneal muaj cua sov rau 1400-1475 ° F (760-800 ° C), ua raws li los ntawm kev ceev ceev.Brazing tuaj yeem ua tiav nyob rau hauv qhov kev daws teeb meem-annealing kub ntau-ua raws li lub quench-lossis los ntawm cua kub ceev hauv qab no ntau yam, tsis muaj kev cuam tshuam rau cov tshuaj-annealed mob.Lub npau taws yog tsim los ntawm kev laus ntawm 550-700 ° F (290-370 ° C) rau ob-rau-peb teev.Nrog rau lwm yam beryllium alloys uas muaj cobalt lossis npib tsib xee, kev kho cua sov yuav txawv.

2. High-conductivity beryllium tooj liab - Cov khoom siv feem ntau siv hauv kev lag luam yog 1.9% beryllium-sib npaug tooj liab.Txawm li cas los xij, nws tuaj yeem muab tau nrog tsawg dua 1% beryllium.Qhov ua tau, qhov tsawg-berylium-cov ntsiab lus alloy yuav tsum tau ua haujlwm rau qhov zoo tshaj plaws brazing tau.Anneal los ntawm cua sov rau 1650-1800 ° F (900-980 ° C), ua raws li los ntawm kev ceev ceev.Lub npau taws yog tsim los ntawm kev laus ntawm 850-950 ° F (455-510 ° C) rau ib mus rau yim teev.

Ntxuav

Kev huv huv yog qhov tseem ceeb rau kev ua tiav brazing.Ua ntej ntxuav lub braze-faying nto kom tshem tawm cov roj thiab roj yog qhov tseem ceeb rau kev sib koom ua ke zoo.Nco ntsoov tias txoj kev ntxuav yuav tsum raug xaiv raws li roj lossis roj chemistry;tsis yog txhua txoj hauv kev tu yuav zoo ib yam los tshem tawm tag nrho cov roj thiab / lossis roj paug.Txheeb xyuas cov khoom paug ntawm qhov chaw, thiab tiv tauj lub chaw tsim khoom kom paub cov kev tu kom raug.Abrasive txhuam los yog acid pickling yuav tshem tawm cov khoom oxidation.

Tom qab ntxuav cov khoom, braze tam sim ntawd nrog flux los muab kev tiv thaiv.Yog tias cov khoom yuav tsum tau khaws cia, cov khoom yuav raug tiv thaiv nrog electroplate ntawm kub, nyiaj los yog npib tsib xee rau 0.0005 "(0.013 hli).Plating tuaj yeem siv los pab txhawb kev ntub dej ntawm beryllium-tooj ​​liab nto los ntawm cov hlau muab tub lim.Ob leeg tooj liab thiab nyiaj yuav plated 0.0005-0.001 "(0.013-0.025mm) los nkaum qhov nyuaj-rau-ntub oxides tsim los ntawm beryllium tooj liab.Tom qab brazing, tshem cov flux residue nrog dej kub los yog txhua yam txhuam kom tsis txhob muaj corrosion.

Kev txiav txim siab tsim

Kev sib koom ua ke yuav tsum tso cai rau kev khiav tawm thiab tseem muab cov capillarity txaus, nyob ntawm qhov muab tub lim-hlau chemistry xaiv.Uniform clearances yuav tsum yog 0.0015-0.005 "(0.04-0.127mm).Txhawm rau pab tshem tawm cov dej ntws los ntawm cov pob qij txha-tshwj xeeb tshaj yog cov kev sib koom ua ke uas siv cov hlua khi los yog cov hlua khi ua ntej-kev txav ntawm ib qho faying nto nrog rau lwm yam thiab / lossis kev co yuav ua haujlwm.Nco ntsoov xam cov clearances rau kev sib koom tsim raws li qhov xav tau ntawm brazing kub.Tsis tas li ntawd, beryllium tooj liab expansion coefficient yog 17.0 x 10-6 / ° C.Xav txog cov thermally induced hom thaum koom nrog cov hlau uas sib txawv thermal-expansion zog.