Inkqubo yokuthengiswa kwe-lead-free reflow ineemfuno eziphezulu kakhulu kwi-PCB kunenkqubo esekelwe kwi-lead.Ukumelana nobushushu kwe-PCB kungcono, i-Tg yokutshintsha kweglasi iphezulu, i-coefficient yokwandisa i-thermal iphantsi, kwaye ixabiso liphantsi.
Iimfuno zokuthengisela i-lead-free reflow for PCB.
Kwi-reflow soldering, i-Tg yipropati ekhethekileyo yeepolymers, emisela ukushisa okubalulekileyo kwezinto eziphathekayo.Ngexesha lenkqubo ye-SMT yokuthengisa, ukushisa kwe-soldering kuphezulu kakhulu kune-Tg ye-substrate ye-PCB, kwaye i-lead-free solder iqondo lokushisa liyi-34 ° C ngaphezu kwe-lead, eyenza kube lula ukuguqulwa kwe-thermal ye-PCB kunye nomonakalo. kumalungu ngexesha lokupholisa.Isiseko semathiriyeli yePCB eneTg ephezulu kufuneka ikhethwe ngokufanelekileyo.
Ngexesha le-welding, ukuba ubushushu buyanda, i-Z-axis ye-multilayer structure PCB ayihambelani ne-CTE phakathi kwe-laminated material, i-glass fiber, kunye ne-Cu kwicala le-XY, eliya kuvelisa uxinzelelo oluninzi kwi-Cu, kwaye iimeko ezinzima, kuya kubangela ukuba i-plating yomngxuma owenziwe ngentsimbi iphuke kwaye ibangele iziphene ze-welding.Kuba kuxhomekeke kwizinto ezininzi eziguquguqukayo, ezifana nenombolo yomaleko we-PCB, ubukhulu, imathiriyeli yelaminate, igophe le-soldering, kunye nokuhanjiswa kweCu, ngejometri, njl.
Kumsebenzi wethu wokwenyani, sithathe amanyathelo athile ukoyisa ukuqhekeka komngxuma owenziwe ngetsimbi webhodi ye-multilayer: umzekelo, i-resin / i-glass fiber isuswa ngaphakathi komngxuma ngaphambi kokuba i-electroplating kwinkqubo ye-recess etching.Ukomeleza amandla okudibanisa phakathi kodonga lwe-metalized hole kunye nebhodi ye-multi-layer.Ubunzulu be-etch yi-13~20µm.
Ubushushu obumiselweyo be-FR-4 substrate PCB yi-240°C.Kwiimveliso ezilula, ukushisa okuphezulu kwe-235 ~ 240 ° C kunokuhlangabezana neemfuno, kodwa kwiimveliso eziyinkimbinkimbi, kunokufuna i-260 ° C ukuba ithengiswe.Ke ngoko, iipleyiti ezityebileyo kunye neemveliso ezintsonkothileyo kufuneka zisebenzise ukumelana nobushushu obuphezulu be-FR-5.Ngenxa yokuba ixabiso le-FR-5 liphezulu, kwiimveliso eziqhelekileyo, isiseko esihlanganisiweyo se-CEMn singasetyenziselwa ukutshintsha i-FR-4 substrates.I-CEMn yisiseko esomeleleyo se-copper-clad laminate enomphezulu kunye nombindi wenziwa ngezinto ezahlukeneyo.I-CEMn ngokufutshane imele iimodeli ezahlukeneyo.
Ixesha lokuposa: Jul-22-2023