Hauv kev tsim cov txheej txheem PCBA, ntau tus neeg yuav khoom yuav ntsib qhov xwm txheej uas SMT cov pob khoom me me SMT nti ua khoom siv tau lees tias yuav ua cov txheej txheem tsis muaj txhuas lossis txheej txheem tsis pub taug txhuas. Dab tsi yog qhov sib txawv ntawm ob lub thev naus laus zis thev naus laus zis? Qhov tseeb, nws tuaj yeem nkag siab hais tias qhov sib txawv ntawm cov txheej txheem tsis muaj taug txhuas thiab cov txheej txheem tsis muaj txheej txheem hauv SMT nti pov thawj txheej txheem yog cov ntsiab lus txhuas hauv cov ntawv txiav ham. Qee tus phooj ywg yuav xav tias cov txheej txheem tsis pub muaj hmoov txhuas tsis muaj tus taug txhuas, uas kuj tsis ncaj ncees lawm. Qhov tseeb, muaj hmoov txhuas nyob rau hauv cov yob tshuaj ntawm cov txheej txheem tsis muaj hmoov txhuas, tab sis nws tshuav rau qhov feem me me.
Ob qhov txheej txheem twg zoo dua? Lingzhuo SMT cov ntaub ntawv pov thawj los qhia rau cov phooj ywg xav tau:
1、 Lub ntsiab lus yaj ntawm cov hmoov txhuas yog 180 ~ 185℃, thiab qhov ua haujlwm kub tau yog li 240 ~ 250℃Cov. Lub ntsiab lus yaj ntawm cov hmoov txhuas-cov xim dawb yog 210 ~ 235℃, thiab qhov ua haujlwm kub yog 245° mus rau 280° C.
2、 Hauv cov txheej txheem SMT SMT, 63/37 Sn / 37 Sn thiab 0.5% Sn, 3% Ag thiab 0.5% Cu yog cov txhuas tsis muaj alloys. Txawm hais tias cov txheej txheem txhuas ua tsis tiav tsis muaj txhuas tag nrho, cov ntsiab lus feem ntau tsis tshua muaj.
3、 Peb txhua tus paub tias tus nqi ntawm tin yog kim dua li cov hlau lead, yog li tus nqi ntawm ham yuav ntau dua tom qab hloov cov hlau lead nrog tin. Qhov no yog ib qho ntawm cov laj thawj tseem ceeb vim li cas cov hlau lead tsis muaj txheej txheem ntau dua cov txheej txheem tsis muaj hmoov txhuas thaum suav cov nqi ntawm SMT cov pob khoom me me SMT nti ua cov khoom lag luam.
4、 Muaj cov hlau lead thev naus laus zis thiab cov txheej txheem tsis pub coj, uas tuaj yeem pom ntawm lub npe. Tab sis tshwj xeeb rau txheej txheem, uas yog siv cov tshuaj cam, cov khoom siv thiab cov khoom siv, xws li yoj soldering rauv, solder muab tshuaj txhuam tshuab, soldering hlau rau phau ntawv vuam, thiab lwm yam.
