1. Cov khoom siv sib txhuam
(1)Kev sib txhuam ntawm cov hlau carbon thiab cov hlau tsis tshua muaj hlau suav nrog kev sib txhuam mos thiab kev sib txhuam nyuaj. Cov khoom siv dav dav hauv kev sib txhuam mos yog cov hlau txhuas tin. Qhov ntub dej ntawm cov hlau no rau cov hlau nce ntxiv nrog rau qhov nce ntawm cov ntsiab lus tin, yog li cov hlau uas muaj cov ntsiab lus tin siab yuav tsum tau siv rau kev sib khi cov pob qij txha. Fesn2 intermetallic compound txheej yuav raug tsim ntawm qhov sib txuas ntawm tin thiab hlau hauv cov hlau txhuas tin. Txhawm rau kom tsis txhob muaj kev tsim cov khoom sib xyaw hauv txheej no, qhov kub thiab txias brazing thiab lub sijhawm tuav yuav tsum tau tswj kom zoo. Lub zog shear ntawm cov hlau carbon sib txuas brazed nrog ntau cov hlau txhuas tin tau qhia hauv Rooj 1. Ntawm lawv, lub zog sib koom ua ke brazed nrog 50% w (SN) yog qhov siab tshaj plaws, thiab lub zog sib koom ua ke welded nrog antimony dawb solder siab dua li nrog antimony.
Rooj 1 lub zog shear ntawm cov pob qij txha carbon steel brazed nrog tin lead solder
Thaum brazing cov hlau carbon thiab cov hlau tsis tshua muaj hlau, feem ntau yog siv cov hlau tooj liab ntshiab, tooj liab zinc thiab nyiaj tooj liab zinc brazing filler hlau. Tooj liab ntshiab muaj qhov melting point siab thiab yooj yim rau oxidize cov hlau hauv paus thaum lub sijhawm brazing. Nws feem ntau yog siv rau kev tiv thaiv roj brazing thiab nqus tsev brazing. Txawm li cas los xij, nws yuav tsum tau sau tseg tias qhov sib txawv ntawm cov pob qij txha brazed yuav tsum tsawg dua 0.05 hli kom tsis txhob muaj teeb meem uas qhov sib txawv ntawm cov pob qij txha tsis tuaj yeem sau vim muaj cov kua dej zoo ntawm tooj liab. Cov hlau carbon thiab cov hlau tsis tshua muaj hlau sib xyaw brazed nrog tooj liab ntshiab muaj zog siab. Feem ntau, lub zog shear yog 150 ~ 215mpa, thaum lub zog tensile yog faib ntawm 170 ~ 340mpa.
Piv nrog rau tooj liab ntshiab, qhov melting point ntawm tooj liab zinc solder txo qis vim yog ntxiv Zn. Yuav kom tiv thaiv Zn evaporation thaum lub sijhawm brazing, ntawm ib sab tes, me ntsis Si tuaj yeem ntxiv rau hauv tooj liab zinc solder; Ntawm qhov tod tes, yuav tsum siv cov txheej txheem cua sov sai, xws li nplaim taws brazing, induction brazing thiab dip brazing. Cov pob qij txha ntawm cov hlau carbon thiab cov hlau tsis tshua muaj hlau brazed nrog tooj liab zinc filler hlau muaj lub zog zoo thiab plasticity. Piv txwv li, lub zog tensile thiab shear zog ntawm cov hlau carbon pob qij txha brazed nrog b-cu62zn solder ncav cuag 420MPa thiab 290mpa. Lub melting point ntawm nyiaj tooj liab chaw nres tsheb solder qis dua li ntawm tooj liab zinc solder, uas yooj yim rau koob vuam. Cov hlau filler no yog tsim rau nplaim taws brazing, induction brazing thiab furnace brazing ntawm carbon hlau thiab cov hlau tsis tshua muaj hlau, tab sis cov ntsiab lus ntawm Zn yuav tsum tau txo kom ntau li ntau tau thaum lub sijhawm furnace brazing, thiab qhov kub yuav tsum tau nce. Brazing carbon hlau thiab cov hlau tsis tshua muaj hlau nrog nyiaj tooj liab zinc filler hlau tuaj yeem tau txais cov pob qij txha nrog lub zog zoo thiab plasticity. Cov ntaub ntawv tshwj xeeb tau teev nyob rau hauv Rooj 2.
Rooj 2 lub zog ntawm cov hlau qis carbon sib txuas brazed nrog nyiaj tooj liab zinc solder
(2) Flux: flux lossis roj tiv thaiv yuav tsum siv rau brazing carbon steel thiab qis alloy steel. Flux feem ntau yog txiav txim siab los ntawm cov hlau filler thiab brazing xaiv. Thaum siv tin lead solder, cov kua sib xyaw ntawm zinc chloride thiab ammonium chloride tuaj yeem siv ua flux lossis lwm yam flux tshwj xeeb. Cov seem ntawm cov flux no feem ntau yog corrosive heev, thiab qhov sib koom ua ke yuav tsum tau ntxuav kom huv si tom qab brazing.
Thaum brazing nrog tooj liab zinc filler hlau, fb301 lossis fb302 flux yuav tsum tau xaiv, uas yog, borax lossis sib tov ntawm borax thiab boric acid; Hauv nplaim brazing, qhov sib tov ntawm methyl borate thiab formic acid kuj tseem siv tau ua brazing flux, uas B2O3 vapor ua lub luag haujlwm ntawm kev tshem tawm zaj duab xis.
Thaum siv cov hlau ua los ntawm nyiaj thiab tooj liab, fb102, fb103 thiab fb104 tuaj yeem xaiv cov flux brazing, uas yog, cov sib xyaw ntawm borax, boric acid thiab qee cov fluorides. Cov seem ntawm cov flux no yog corrosive rau qee qhov thiab yuav tsum tau muab tshem tawm tom qab brazing.
2. Kev siv tshuab txhuam
Qhov chaw uas yuav tsum tau welded yuav tsum tau ntxuav los ntawm kev siv tshuab lossis tshuaj lom neeg kom ntseeg tau tias cov yeeb yaj kiab oxide thiab cov organic raug tshem tawm tag nrho. Qhov chaw ntxuav yuav tsum tsis txhob ntxhib dhau thiab yuav tsum tsis txhob lo rau cov hlau tawg lossis lwm yam av.
Cov hlau carbon thiab cov hlau uas tsis tshua muaj hlau sib xyaw ua ke tuaj yeem siv ntau txoj kev sib xyaw ua ke. Thaum lub sijhawm sib xyaw ua ke, yuav tsum siv cov nplaim taws nruab nrab lossis txo me ntsis. Thaum lub sijhawm ua haujlwm, yuav tsum tsis txhob siv cov hlau filler thiab cov nplaim taws kom sov ncaj qha li ntau tau. Cov txheej txheem kub ceev xws li induction brazing thiab dip brazing yog qhov tsim nyog rau kev sib xyaw ua ke ntawm cov hlau quenched thiab tempered. Tib lub sijhawm, yuav tsum xaiv quenching lossis brazing ntawm qhov kub qis dua tempering kom tiv thaiv kev ua kom cov hlau hauv paus mos. Thaum sib xyaw ua ke cov hlau tsis tshua muaj hlau sib xyaw ua ke muaj zog hauv huab cua tiv thaiv, tsis yog tsuas yog xav tau cov roj ntshiab xwb, tab sis kuj yuav tsum siv cov roj flux kom ntseeg tau tias cov hlau filler ntub thiab nthuav dav rau ntawm qhov chaw ntawm cov hlau hauv paus.
Cov kua dej seem tuaj yeem raug tshem tawm los ntawm kev siv tshuaj lom neeg lossis kev siv tshuab. Cov kua dej seem ntawm cov kua dej organic brazing tuaj yeem so lossis ntxuav nrog roj av, cawv, acetone thiab lwm yam organic solvents; Cov kua dej seem ntawm cov kua dej corrosive xws li zinc chloride thiab ammonium chloride yuav tsum tau neutralized hauv NaOH aqueous kua ua ntej, thiab tom qab ntawd ntxuav nrog dej kub thiab txias; Boric acid thiab boric acid flux residues nyuaj rau tshem tawm, thiab tsuas yog daws tau los ntawm kev siv tshuab lossis kev siv dej ntev hauv dej nce.
Lub sijhawm tshaj tawm: Lub Rau Hli-13-2022