Qee lub sij hawm yuav muaj qee qhov kev ua haujlwm tsis zoo hauv cov txheej txheem ntawmSMT tshuab, tin hlaws yog ib qho ntawm lawv, los daws qhov teeb meem, peb yuav tsum xub paub qhov ua rau ntawm qhov teeb meem.Solder beading yog nyob rau hauv lub solder paste slump los yog nyob rau hauv tus txheej txheem ntawm nias tawm ntawm lub ncoo tshwm sim.Thaumreflow qhov cubsoldering, solder paste yog cais los ntawm lub ntsiab deposit thiab pooled nrog ntau tshaj solder paste los ntawm lwm yam ntaub ntawv, los ntawm ib sab ntawm lub cev tivthaiv los ua loj hlaws dai, los yog nyob rau hauv lub hauv paus ntawm cov khoom.Kev tshem tawm cov tin hlaws kom deb li deb tau los ntawm kev tshem tawm ncaj qha ntawm txoj kev, nyob rau hauv cov txheej txheem ntau lawm yuav tsum xyuam xim rau, yuav zam tau.Cov hauv qab no yog txhawm rau txheeb xyuas cov xwm txheej twg yuav tsim cov hlaws dai:
I. Hlau Mesh
1. Hlau mesh qhib ncaj qha raws li qhov loj ntawm lub ncoo qhib yuav ua rau tin hlaws tshwm sim hauv cov txheej txheem ntawm kev ua haujlwm.
2. Yog hais tias lub thickness ntawm cov hlau net yog tuab heev, nws tseem tuaj yeem ua rau lub cev qhuav dej, uas yuav ua rau cov tin hlaws dai.
3. Yog lub siab ntawmxaiv thiab tso tshuabyog siab dhau lawm, cov tshuaj txhuam hniav yuav yooj yim extruded rau cov txheej txheem solder hauv qab ntawm cov khoom, thiab cov tshuaj txhuam hniav yuav yaj thiab khiav ib ncig ntawm cov khoom siv los ua cov hlaws hlaws thaum lub qhov cub reflow.
II.Lub solder muab tshuaj txhuam
1. Solder paste yam tsis muaj qhov kub thiab txias rov ua haujlwm hauv theem preheating yuav txaws tshwm sim los tsim cov hlaws dai.
2. Qhov me me ntawm cov hmoov hlau hmoov nyob rau hauv cov tshuaj txhuam hniav, qhov loj dua qhov chaw ntawm tag nrho cov tshuaj txhuam hniav, uas ua rau ntau dua oxidation degree ntawm cov hmoov zoo, yog li qhov tshwm sim ntawm cov hlaws hlaws yog intensified.
3. Qhov siab dua ntawm oxidation degree ntawm cov hmoov hlau hauv cov tshuaj txhuam hniav, qhov ntau dua cov hmoov hlau hmoov sib txuas thaum lub sij hawm vuam, cov tshuaj txhuam thiab cov ntaub qhwv thiab SMT cov khoom tsis yooj yim rau infiltrate, uas ua rau txo cov solderability.
4. Tus nqi ntawm flux thiab tus nqi ntawm active flux yog ntau dhau, uas yuav ua rau lub zos vau ntawm solder paste thiab tin hlaws dai.Thaum qhov kev ua ntawm flux tsis txaus, qhov oxidized tsis tuaj yeem raug tshem tawm tag nrho, uas tseem yuav ua rau cov hlaws dai hauv kev ua haujlwm ntawm thaj chaw ua haujlwm.
5. Cov ntsiab lus hlau hauv kev ua tiav ntawm cov tin paste feem ntau yog 88% mus rau 92% ntawm cov ntsiab lus hlau thiab qhov sib piv, qhov ntim piv ntawm li 50%, nce cov ntsiab lus hlau tuaj yeem ua rau cov hmoov hlau ua kom zoo dua, yog li ntawd. nws yooj yim dua los ua ke thaum melting.
Post lub sij hawm: Sep-18-2021