Ukuxutywa kwe-aluminiyam kunye ne-alloys ye-aluminium

1. Ukuba nesibindi

Ipropathi yokuqhafaza kwe-aluminium kunye ne-aluminium alloys ihlwempuzekile, ngokukodwa kuba ifilimu ye-oxide ebusweni kunzima ukuyisusa. IAluminiyam inobudlelwane obukhulu beoksijini. Kulula ukwenza ifilimu eshinyeneyo, ezinzileyo kunye nephezulu yokunyibilika kwe-oxide ye-Al2O3 kumphezulu. Ngelo xesha, i-aluminium alloys equkethe i-magnesium nayo iya kwenza ifilimu ye-oxide ezinzileyo kakhulu ye-MgO. Baya kuthintela kakhulu ukumanzisa kunye nokusabalalisa i-solder. Kwaye kunzima ukususa. Ngexesha lokugcoba, inkqubo yokuqhafaza inokuthi iqhutywe kuphela nge-flux efanelekileyo.

Okwesibini, ukusebenza kwe-aluminium kunye ne-aluminium alloy brazing kunzima. I-melting point ye-aluminium kunye ne-aluminium alloy ayifani kakhulu naleyo yensimbi yokuqhafaza esetyenzisiweyo. Uluhlu olukhethwayo lobushushu lokubhengeza lumxinwa kakhulu. Ulawulo oluncinci lweqondo lokushisa olungafanelekanga lulula ukubangela ukushisa okanye ukunyibilika kwesiseko sesinyithi, okwenza inkqubo yokuqhayisa inzima. Ezinye ii-alloys ze-aluminiyam eziqiniswe kunyango lobushushu ziya kubangela ukuba izinto ezithambileyo zithobe njengokuguga okanye ukucima ngenxa yokufudumeza kwebrazi, okuya kunciphisa iipropathi zebrazed joints. Ngexesha lokuvutha komlilo, kunzima ukugweba ubushushu kuba umbala we-aluminium alloy awutshintshi ngexesha lokufudumala, okwandisa iimfuno zenqanaba lokusebenza komsebenzisi.

Ngaphezu koko, ukuxhathisa ukubola kwe-aluminiyam kunye ne-aluminium alloy brazed joints ichaphazeleka ngokulula zizinyithi zokuzalisa kunye ne-fluxes. Amandla e-electrode ye-aluminiyam kunye ne-aluminium alloy yahluke kakhulu kwi-solder, enciphisa ukuxhathisa ukubola kwe-joint, ngakumbi kwi-solder ethambileyo edibeneyo. Ukongeza, uninzi lwee-fluxes ezisetyenzisiweyo kwi-brazing ye-aluminiyam kunye ne-alloys ye-aluminium inokonakala okuqinileyo. Nangona zihlanjululwe emva kokuqhaqha, impembelelo ye-fluxes kwi-corrosion resistance of joints ayiyi kupheliswa ngokupheleleyo.

2. Izinto zokubrasha

(1) Ukuxutywa kwe-aluminiyam kunye ne-aluminium alloys yindlela engavamile ukusetyenziswa, kuba ukubunjwa kunye ne-electrode ye-brazing filler metal kunye nesiseko sesinyithi sihluke kakhulu, okulula ukubangela ukubola kwe-electrochemical of joint. I-solder ethambileyo kakhulu ithatha i-zinc esekelwe kwi-solder kunye ne-tin lead solder, enokuthi yohlulwe ibe yi-solder ephantsi yobushushu (150 ~ 260 ℃), i-solder yobushushu obuphakathi (260 ~ 370 ℃) kunye ne-solder yobushushu obuphezulu (370 ~ 430 ℃) ngokoluhlu lobushushu. Xa i-tin lead solder isetyenzisiwe kwaye ubhedu okanye i-nickel ifakwe ngaphambili kwi-aluminium surface ukuze idibanise, i-corrosion kwi-interface edibeneyo inokuthintelwa, ukwenzela ukuba kuphuculwe ukuxhathisa kwe-corrosion ye-joint.

I-Brazing ye-aluminium kunye ne-aluminium alloys isetyenziswa ngokubanzi, njengesikhokelo sokucoca, i-evaporator, i-radiator kunye nezinye izinto. Kuphela ziintsimbi zokuzalisa ezisekwe kwi-aluminiyam ezinokusetyenziselwa ukubrawuza i-aluminiyam kunye ne-alloys ye-aluminium, phakathi kwayo i-aluminium silicon filler metal zezona zisetyenziswa kakhulu. Umda othile wokusetyenziswa kunye namandla okucheba amalunga aqhagamshelweyo aboniswe kwiThebhile 8 kunye netheyibhile 9 ngokulandelelanayo. Nangona kunjalo, indawo yokunyibilika yale solder isondele kwisiseko setsimbi, ngoko ke izinga lokushisa lokufudumala kufuneka lilawulwe ngokungqongqo kwaye lichaneke ngokuchanekileyo ngexesha lokugcoba ukuphepha ukugqithisa okanye ukunyibilika kwesiseko sesinyithi.

Itheyibhile yesi-8 yokusetyenziswa komda wesinyithi sokuzalisa i-aluminiyam kunye ne-aluminium alloys

Itheyibhile ye-9 yamandla okucheba ye-aluminiyam kunye ne-aluminium alloy joints ezidityaniswe nge-aluminiyam ye-silicon yokuzalisa isinyithi

I-aluminiyam i-silicon solder idla ngokunikezelwa ngendlela yomgubo, intlama, ucingo okanye iphepha. Kwezinye iimeko, iipleyiti ze-solder ezihlanganisiweyo kunye ne-aluminiyam njengengundoqo kunye ne-aluminium ye-silicon solder njengoko i-cladding isetyenziswa. Olu hlobo lwe-solder composite plate yenziwe ngendlela ye-hydraulic kwaye isoloko isetyenziswa njengenxalenye yamacandelo okubrawuza. Ngexesha lokugcoba, isinyithi sokuzalisa i-brazing kwi-plate edibeneyo iyancibilika kwaye igeleza phantsi kwesenzo se-capillary kunye ne-gravity yokuzalisa i-gap edibeneyo.

(2) I-Flux kunye negesi yokukhusela i-aluminium kunye ne-aluminium alloy brazing, i-flux ekhethekileyo isoloko isetyenziselwa ukususa ifilimu. I-organic flux esekelwe kwi-triethanolamine, efana ne-fs204, isetyenziswa kunye ne-solder ethambileyo yobushushu obuphantsi. Inzuzo yalo mbhobho kukuba inempembelelo encinci ye-corrosion kwisiseko sesinyithi, kodwa iya kuvelisa inani elikhulu legesi, eliya kuchaphazela ukumanzisa kunye ne-caulking ye-solder. I-flux esebenzayo esekelwe kwi-zinc chloride, efana ne-fs203 kunye ne-fs220a, isetyenziselwa ubushushu obuphakathi kunye ne-solder ethambileyo ephezulu. I-flux esebenzayo iyingozi kakhulu, kwaye intsalela yayo kufuneka isuswe emva kokuqhaqha.

Okwangoku, i-brazing ye-aluminium kunye ne-aluminium alloys isalawulwa ngokususwa kwefilimu ye-flux. I-brazing flux esetyenzisiweyo iquka i-chloride esekelwe kwi-flux kunye ne-fluoride based flux. I-Chloride esekelwe kwi-flux inamandla amakhulu okususa ifilimu ye-oxide kunye ne-fluidity efanelekileyo, kodwa inempembelelo enkulu eyingozi kwisiseko sesinyithi. Intsalela yayo kufuneka isuswe ngokupheleleyo emva kokubrawuza. I-fluoride esekelwe kwi-fluoride luhlobo olutsha lwe-flux, enefuthe elihle lokususa ifilimu kwaye akukho mhlwa kwisiseko sesinyithi. Nangona kunjalo, inendawo ephezulu yokunyibilika kunye nokuzinza okuphantsi kwe-thermal, kwaye inokusetyenziswa kuphela nge-aluminium solder ye-silicon.

Xa ukubetha i-aluminium kunye ne-aluminium alloys, i-vacuum, i-neutral okanye i-inert atmosphere isoloko isetyenziswa. Xa kusetyenziswa i-vacuum brazing, idigri yevacuum iya kufikelela ngokubanzi kumyalelo we-10-3pa. Xa i-nitrogen okanye i-argon gas isetyenziselwa ukukhusela, ucoceko kufuneka lube phezulu kakhulu, kwaye indawo yombethe kufuneka ibe ngaphantsi kwe -40 ℃

3. Iteknoloji yokubrawuza

I-Brazing ye-aluminium kunye ne-aluminium alloys ineemfuno eziphezulu zokucocwa kwendawo yokusebenza. Ukuze ufumane umgangatho omhle, i-oyile ye-oyile kunye nefilimu ye-oxide phezu komhlaba kufuneka isuswe ngaphambi kokutshisa. Susa i-oil stain phezu komhlaba kunye nesisombululo se-Na2CO3 samanzi kwiqondo lokushisa lama-60 ~ 70 ℃ nge-5 ~ 10min, uze uhlambulule ngamanzi acocekileyo; Ifilimu ye-oxide ye-surface inokususwa ngokutshiza nge-NaOH isisombululo samanzi kwiqondo lokushisa kwe-20 ~ 40 ℃ ye-2 ~ 4min, kwaye emva koko ihlanjwe ngamanzi ashushu; Emva kokususa i-oil stain kunye nefilimu ye-oxide phezu komhlaba, i-workpiece iya kunyangwa nge-HNO3 isisombululo se-aqueous ye-gloss ye-2 ~ 5min, emva koko ihlambuluke emanzini asebenzayo kwaye ekugqibeleni yomiswe. Isixhobo sokusebenza esinyangwa ngezi ndlela asiyi kuchukunyiswa okanye singcoliswe ngolunye ukungcola, kwaye siya kugqunywa ngaphakathi kwe-6 ~ 8h. Kungcono ukugcoba ngokukhawuleza ukuba kunokwenzeka.

Iindlela zokubethelwa kwe-aluminium kunye ne-aluminium alloys ikakhulu zibandakanya ukuvutha komlilo, i-soldering iron brasing kunye ne-furnace brazing. Ezi ndlela ngokuqhelekileyo zisebenzisa i-flux kwi-brazing, kwaye zineemfuno ezingqongqo kwiqondo lokushisa lokushisa kunye nexesha lokubamba. Ngexesha lokugqabhuka kwedangatye kunye nokutywinwa kwentsimbi, kunqande ukufudumeza umsinga ngokuthe ngqo ngomthombo wobushushu ukunqanda ubushushu bobushushu kunye nokusilela. Ekubeni i-aluminiyam inokunyibilika kwi-solder ethambileyo enomxholo ophezulu we-zinc, ukufudumeza kufuneka kumiswe emva kokuba i-joint yenziwe ukuphepha isiseko sentsimbi. Kwezinye iimeko, ukunyanzeliswa kwe-aluminium kunye ne-aluminium alloys ngamanye amaxesha ayisebenzisi i-flux, kodwa isebenzisa iindlela ze-ultrasonic okanye ze-scraping ukususa ifilimu. Xa usebenzisa i-scraping ukususa ifilimu yokugcoba, qale ufudumeze i-workpiece kwiqondo lokushisa lokutshisa, kwaye emva koko ukhuphe inxalenye ye-brazing ye-workpiece kunye nesiphelo sentonga ye-solder (okanye isixhobo sokukrala). Ngelixa uphula ifilimu ye-oxide yomhlaba, isiphelo se-solder siya kunyibilika kwaye simanzise isiseko sesinyithi.

Iindlela zokubrawuza ze-aluminiyam kunye ne-aluminium alloys ikakhulu zibandakanya ukuvutha komlilo, ukuvutha kwesithando somlilo, i-dip brazing, i-vacuum brazing kunye ne-gas shielded brazing. Ukuvutha komlilo kusetyenziswa kakhulu kwizixhobo ezincinci zokusebenza kunye nemveliso yeqhekeza elinye. Ukuze ugweme ukungaphumeleli kwe-flux ngenxa yoqhagamshelwano phakathi kokungcola kwi-acetylene kunye ne-flux xa usebenzisa i-oxyacetylene flame, kuyafaneleka ukusebenzisa i-petroli edibeneyo yomlilo womoya kunye nokunciphisa okuncinci ukukhusela i-oxidation yesiseko sesinyithi. Ngethuba lokutshisa okuthe ngqo, i-brazing flux kunye ne-filler metal ingafakwa kwindawo edibeneyo ngaphambili kwaye ishushu ngexesha elifanayo kunye nomsebenzi; I-workpiece inokufudunyezwa kwiqondo lokushisa lokuqala, kwaye emva koko i-solder editywe nge-flux ingathunyelwa kwindawo yokuqhayisa; Emva kokuba i-flux kunye ne-filler metal iyancibilika, i-flame yokufudumeza iya kususwa ngokukhawuleza emva kokuba isinyithi sokuzalisa sigcwaliswe ngokulinganayo.

Xa i-aluminiyam kunye ne-alloy ye-alloy yokutshisa kwisithando somoya, isinyithi sokugcwalisa isinyithi siya kulungiswa kwangaphambili, kwaye i-brazing flux iya kunyibilika emanzini adibeneyo ukuze kulungiswe isisombululo esinzima kunye ne-concentration ye-50% ~ 75%, kwaye emva koko igqunywe okanye itshizwe kwindawo yokutshisa. Umlinganiselo ofanelekileyo we-powder brazing flux unokugqunywa kwi-brazing filler metal kunye ne-brazing surface, emva koko i-weldment edibeneyo iya kufakwa kwisithando somlilo sokufudumeza ukutshisa. Ukuze uthintele isiseko sesinyithi ekugqithiseni okanye nokuba sinyibilike, ubushushu bokufudumala kufuneka bulawulwe ngokungqongqo.

I-paste okanye i-foil solder isetyenziswa ngokubanzi ukudipha i-aluminiyam kunye ne-alloys ye-aluminium. Isixhobo sokusebenza esidityanisiweyo siya kufudunyezwa ngaphambi kokuba sitshise ukwenza iqondo lobushushu libe kufutshane neqondo lobushushu, emva koko lintywiliselwe kwi-brazing flux for brazing. Ngethuba lokutshisa, ukushisa kwe-brazing kunye nexesha lokubhobhoza kuya kulawulwa ngokungqongqo. Ukuba iqondo lokushisa liphezulu kakhulu, isiseko sesinyithi silula ukuchithwa kwaye i-solder kulula ukulahleka; Ukuba iqondo lokushisa liphantsi kakhulu, i-solder ayincibiliki ngokwaneleyo, kwaye izinga lokubhobhoza liyancipha. Ukushisa okutshisayo kuya kugqitywa ngokohlobo kunye nobukhulu besiseko sesinyithi, ukubunjwa kunye nendawo yokunyibilika kwentsimbi yokuzalisa, kwaye ngokuqhelekileyo phakathi kobushushu be-liquid yentsimbi yokuzalisa kunye nobushushu be-solidus yesiseko sesinyithi. Ixesha lokuntywila le-workpiece kwi-bath flux kufuneka liqinisekise ukuba i-solder inokunyibilika ngokupheleleyo kwaye ihambe, kwaye ixesha elixhasayo akufanele libe lide kakhulu. Ngaphandle koko, i-silicon element kwi-solder inokusasazeka kwisiseko sesinyithi, isenza isiseko sesinyithi kufuphi nomthungo sibe brittle.

Kwi-vacuum brazing ye-aluminium kunye ne-aluminium alloys, ii-activators zetsimbi zihlala zisetyenziselwa ukuguqula ifilimu ye-oxide ye-aluminium kunye nokuqinisekisa ukumanzisa kunye nokusabalalisa i-solder. I-Magnesium inokusetyenziswa ngokuthe ngqo kwi-workpiece ngendlela yeengqungquthela, okanye ifakwe kwindawo yokuqhafaza ngendlela ye-steam, okanye i-magnesium inokongezwa kwi-aluminium solder ye-silicon njenge-alloy element. Kwi-workpiece enesakhiwo esiyinkimbinkimbi, ukwenzela ukuba kuqinisekiswe isiphumo esipheleleyo somphunga we-magnesium kwisiseko sesinyithi kunye nokuphucula umgangatho wokuqhafaza, amanyathelo okukhusela asekuhlaleni ahlala ethathwa, oko kukuthi, i-workpiece ibekwe kuqala kwibhokisi yensimbi engenasici (eyaziwa ngokuba yibhokisi yenkqubo), kwaye emva koko ifakwe kwisithando somlilo sokufudumeza ukutshisa. I-Vacuum Brazed Aluminiyam kunye ne-aluminium alloy joints inomphezulu ogudileyo kunye neendawo ezixineneyo zebrazed, kwaye akukho mfuneko yokuba zicocwe emva kokugqatswa; Nangona kunjalo, izixhobo ze-vacuum brazing zibiza kakhulu, kwaye umphunga we-magnesium ungcolisa isithando somlilo ngokunzulu, ngoko kufuneka sicocwe kwaye sigcinwe rhoqo.

Xa i-aluminium ye-brazing kunye ne-aluminium alloys kwi-neutral okanye i-inert atmosphere, i-activator ye-magnesium okanye i-flux ingasetyenziselwa ukususa ifilimu. Xa i-activator ye-magnesium isetyenziselwa ukususa ifilimu, inani le-magnesium efunekayo liphantsi kakhulu kunelo lokutshiza kwe-vacuum. Ngokuqhelekileyo, i-w (mg) imalunga ne-0.2% ~ 0.5%. Xa umxholo we-magnesium uphezulu, umgangatho wokudibanisa uya kuncitshiswa. Indlela ye-NOCOLOK yokubhuqa usebenzisa ifluoride flux kunye nokhuseleko lwenitrogen yindlela entsha ephuhliswe ngokukhawuleza kwiminyaka yakutshanje. Ekubeni intsalela ye-fluoride flux ayifuni ukufuma kwaye ayinayo i-aluminium, inkqubo yokususa i-flux i-residue emva kokuqhawula i-brazing ingashiywa. Ngaphantsi kokukhuselwa kwe-nitrogen, kuphela umlinganiselo omncinci we-fluoride flux kufuneka ugqunywe, isinyithi sokuzalisa sinokumanzisa kakuhle isiseko sesinyithi, kwaye kulula ukufumana amalunga adityanisiweyo aphezulu. Okwangoku, le ndlela yokugaya i-NOCOLOK isetyenziswe kwimveliso yobuninzi be-radiator ye-aluminium kunye nezinye izinto.

Kwi-aluminiyam kunye ne-alloy ye-aluminiyam ebrazed kunye ne-fluoride flux, intsalela ye-flux kufuneka isuswe ngokupheleleyo emva kokubrawuza. Intsalela ye-organic brazing flux ye-aluminium inokuhlanjwa kunye nezisombululo eziphilayo ezifana ne-methanol kunye ne-trichlorethylene, ingathathi hlangothi ngesisombululo se-sodium hydroxide yamanzi, kwaye ekugqibeleni ihlanjululwe ngamanzi ashushu nabandayo. I-chloride yintsalela ye-brazing flux ye-aluminium, enokususwa ngokweendlela ezilandelayo; Okokuqala, cwilisa emanzini atshisayo kwi-60 ~ 80 ℃ ye-10min, ucoce ngokucophelela i-residu kwi-brazed joint kunye ne-brush, kwaye uyihlambulule ngamanzi abandayo; Emva koko yicwilise kwi-15% ye-nitric acid yesisombululo se-aqueous ye-30min, kwaye ekugqibeleni uyihlambulule ngamanzi abandayo.