I-reflow soldering yeyona ndlela isetyenziswa kakhulu kwi-welding ye-surface component kwishishini le-SMT.Enye indlela yokudibanisa i-wave soldering.I-Reflow soldering ifanelekile kumacandelo e-chip, ngelixa i-soldering ye-wave ifanelekile kwi-pin electronic components.
I-Reflow soldering nayo yinkqubo yokuphinda ithengise.Umgaqo wayo kukushicilela okanye ukutofa isixa esifanelekileyo sokuncamathisela kwi-PCB pad kwaye uncamathisele icandelo elihambelanayo le-SMT patch, emva koko usebenzise ukufudumeza umoya oshushu wesithando somlilo ukunyibilikisa intlama ye-solder, kwaye ekugqibeleni wenze i-solder ethembekileyo edibeneyo. ngokupholisa.Qhagamshela amacandelo ngePCB pad ukudlala indima yoqhagamshelo ngoomatshini kunye noqhagamshelo lombane.Ngokuqhelekileyo, i-reflow soldering ihlulwe ibe ngamanqanaba amane: ukushisa kwangaphambili, ubushushu obuqhubekayo, ukugeleza kwakhona kunye nokupholisa.
1. Indawo yokufudumala
Indawo yokufudumala: linqanaba lokuqala lokufudumala kwemveliso.Injongo yalo kukufudumala ngokukhawuleza imveliso kwiqondo lokushisa lokushisa kwaye isebenze i-solder paste flux.Kwangaxeshanye, ikwayindlela yokufudumeza eyimfuneko ukuphepha ukulahleka kobushushu obumdaka bamacandelo abangelwa kukufudumeza okuphezulu kobushushu obukhawulezayo ngexesha lokuntywiliselwa kwetin.Ngoko ke, impembelelo yokunyuka kweqondo lokushisa kwimveliso ibaluleke kakhulu kwaye kufuneka ilawulwe ngaphakathi koluhlu olufanelekileyo.Ukuba ikhawuleza kakhulu, iya kuvelisa ukothuka kwe-thermal, i-PCB kunye namacandelo aya kuchatshazelwa luxinzelelo lwe-thermal kwaye abangele umonakalo.Ngelo xesha, i-solvent kwi-solder paste iya kuguquguquka ngokukhawuleza ngenxa yokufudumala ngokukhawuleza, okubangelwa ukutshiza kunye nokwakhiwa kweentsimbi ze-solder.Ukuba icotha kakhulu, i-solder paste solvent ayiyi kuguquguquka ngokupheleleyo kwaye ichaphazele umgangatho we-welding.
2. Ummandla wobushushu rhoqo
Ummandla wobushushu othe rhoqo: injongo yawo kukuzinzisa ubushushu bento nganye kwi-PCB nokufikelela kwisivumelwano kangangoko ukunciphisa umahluko wobushushu phakathi kwento nganye.Kweli nqanaba, ixesha lokufudumeza lecandelo ngalinye lide kakhulu, kuba amacandelo amancinci aya kufikelela kwibhalansi kuqala ngenxa yokufunxa ubushushu obuncinci, kwaye amacandelo amakhulu adinga ixesha elaneleyo lokubamba amacandelo amancinci ngenxa yokufunxa ubushushu obukhulu, kwaye aqinisekise ukuba i-flux. kwi-solder paste iguquguquke ngokupheleleyo.Kule nqanaba, phantsi kwesenzo se-flux, i-oxide kwi-pad, ibhola ye-solder kunye nepini yecandelo iya kususwa.Ngelo xesha, i-flux iya kuphinda isuse i-oil stain ebusweni becandelo kunye ne-pad, yandise indawo ye-welding kwaye ithintele icandelo ukuba liphinde lifakwe kwi-oxidized.Emva kwesi sigaba, onke amacandelo aya kugcina ubushushu obufanayo okanye obufanayo, kungenjalo i-welding engalunganga ingenzeka ngenxa yomahluko ogqithisileyo wobushushu.
Iqondo lobushushu kunye nexesha lobushushu obuqhubekayo buxhomekeke kubunzima boyilo lwePCB, umahluko weentlobo zecandelo kunye nenani lamacandelo.Ngokuqhelekileyo ikhethwa phakathi kwe-120-170 ℃.Ukuba iPCB intsonkothile ngokukodwa, iqondo lobushushu lendawo yobushushu elingaguqukiyo kufuneka limiselwe ngerosin ethambileyo yobushushu njengesalathiso, ukuze kuncitshiswe ixesha le-welding yendawo yokuqukuqela kwakhona kwicandelo lamva.Indawo yobushushu obungaguqukiyo yenkampani yethu ikhethwa ngokubanzi kwi-160 ℃.
3. Indawo ye-Reflux
Injongo yommandla wokubuyisela kwakhona kukwenza i-solder paste inyibilike kwaye imanzise i-pad kumphezulu we-element ukuba idityaniswe.
Xa ibhodi PCB ingena kwindawo reflow, iqondo lobushushu liya kunyuka ngokukhawuleza ukwenza i-solder paste ifikelele kwimo yokunyibilika.Indawo yokunyibilika yokuncamathelisa i-solder SN: 63 / Pb: 37 yi-183 ℃, kunye ne-lead-free solder paste SN: 96.5/ag: 3 / Cu: 0. Indawo yokunyibilika ye-5 yi-217 ℃.Kule candelo, i-heater inika ubushushu obuninzi, kwaye ukushisa kwesithando somlilo kuya kumiselwa phezulu, ukwenzela ukuba i-solder paste iqondo lokushisa likhuphuke ngokukhawuleza kwiqondo lokushisa eliphezulu.
Iqondo lobushushu eliphakamileyo legophe le-soldering le-reflow limiselwa ngokubanzi kwindawo yokunyibilika ye-solder paste, ibhodi yePCB kunye nobushushu obuxhathisa ubushushu becandelo ngokwalo.Ubushushu obuphezulu beemveliso kwindawo yokubuyisela kwakhona iyahluka ngokohlobo lwe-solder paste esetyenzisiweyo.Xa sithetha ngokubanzi, obona bushushu bencopho bencopho yentlama ye-solder engenalothe buqheleke bungama-230 ~ 250 ℃, kunye nobokuncamatheliswa kwe-solder yelothe ngokuqhelekileyo yi-210 ~ 230 ℃.Ukuba iqondo lokushisa eliphakamileyo liphantsi kakhulu, kulula ukuvelisa i-welding ebandayo kunye nokumanzisa okwaneleyo kwamalungu e-solder;Ukuba iphezulu kakhulu, i-epoxy resin type substrate kunye namalungu eplastiki athambekele ekuphekeni, iPCB ibe namagwebu kunye ne-delamination, kwaye iya kukhokelela ekwakhiweni kweekhompawundi zentsimbi ze-eutectic ezigqithisileyo, zenze ijoyinti ye-solder ibe brittle kwaye amandla okuwelda abe buthathaka, okuchaphazela iimpawu zomatshini wemveliso.
Kufuneka kugxininiswe ukuba i-flux kwi-paste ye-solder kwindawo yokubuyisela iluncedo ekukhuthazeni ukumanzisa phakathi kwe-solder paste kunye necandelo le-welding end kunye nokunciphisa uxinzelelo oluphezulu lwe-solder paste ngeli xesha, kodwa ukukhuthazwa kwe-flux kuya . kuthintelwe ngenxa yentsalela yeoksijini kunye neeoksidi zomgangatho wesinyithi kwisithando somlilo.
Ngokubanzi, ijiko elilungileyo lobushushu bomlilo kufuneka lihlangane ukuba iqondo lobushushu lencopho yenqaku ngalinye kwi-PCB kufuneka lihambelane kangangoko kunokwenzeka, kwaye umahluko kufuneka ungadluli i-10 degrees.Kuphela ngale ndlela sinokuqinisekisa ukuba zonke izenzo ze-welding zigqitywe kakuhle xa imveliso ingena kwindawo yokupholisa.
4. Indawo yokupholisa
Injongo yendawo yokupholisa kukupholisa ngokukhawuleza i-solder paste particles kunye nokukhawuleza ukwenza i-solder ekhanyayo kunye ne-radian epholileyo kunye nenani elipheleleyo le-tin.Ke ngoko, iifektri ezininzi ziya kulawula indawo yokupholisa kakuhle, kuba ilungele ukwenza i-solder joint form.Xa sithetha ngokubanzi, isantya sokupholisa esikhawuleza kakhulu siyakuyenza ibesemva kwexesha kakhulu ukuba intlama ye-solder etyhidiweyo iphole kwaye ithintele, okukhokelela ekuhleni, ekuloleni kunye nakwimibhobho edityanisiweyo yesoda.Izinga lokupholisa eliphantsi kakhulu liya kwenza ukuba izinto ezisisiseko ze-PCB pad zidibanise kwintlama ye-solder, zenze i-solder joint rough, i-welding engenanto kunye ne-solder ebumnyama.Ngaphezu koko, zonke iimagazini zesinyithi ekupheleni kwecandelo ziya kunyibilika kwindawo edibeneyo ye-solder, okubangela ukwala okumanzi okanye ukuwelda okungalunganga kwi-solder yecandelo ekupheleni, Kuchaphazela umgangatho we-welding, ngoko izinga lokupholisa elihle libaluleke kakhulu kwi-solder joint forming. .Ngokubanzi, umthengisi we-solder paste uya kucebisa ireyithi yokupholisa edibeneyo ye-solder ≥ 3 ℃ / s.
Ishishini laseChengyuan yinkampani ekhethekileyo ekuboneleleni ngezixhobo zemveliso ze-SMT kunye nePCBA.Ikubonelela ngesona sisombululo sifanelekileyo.Ineminyaka emininzi yemveliso kunye namava e-R & D.Iingcali zobuchwephesha zibonelela ngesikhokelo sokufakela kunye nenkonzo emva kokuthengisa kwindlu ngendlu, ukuze ungabinaxhala ekhaya.
Ixesha lokuposa: Apr-09-2022