Mbiri Yotsitsimula Yopanda Kutsogola: Mtundu wonyowa motsutsana ndi mtundu wa Slumping

Reflow soldering ndi njira yomwe phala la solder limatenthedwa ndikusintha kukhala losungunuka kuti lilumikize zikhomo ndi ma PCB pamodzi kwamuyaya.

Pali masitepe/magawo anayi ochitira izi - kutenthetsa, kuthira, kuyambiranso ndi kuziziritsa.

Pazambiri zachikhalidwe zamtundu wa trapezoidal pa phala laulere la solder lomwe Bittele amagwiritsa ntchito pokonzekera msonkhano wa SMT:

1. Preheating zone: Preheat nthawi zambiri amatanthauza kuonjezera kutentha kwa kutentha kwa 150 ° C ndi kuchokera 150 ° C mpaka 180 C. Kutentha kwa kutentha kuchokera ku 150 ° C kumakhala kosakwana 5 ° C / sec (pa 1.5 ° C ~ 3 ° C / sec), ndipo nthawi yapakati pa 150 ° C mpaka 180 ° C ndi kuzungulira 60 ~ 220 sec.Phindu la kutentha pang'onopang'ono ndikulola kuti zosungunulira ndi madzi mu nthunzi ya phala zituluke pa nthawi yake.Imalolanso zigawo zazikulu kutenthetsa nthawi zonse ndi tizigawo tating'ono tating'ono.
2. Malo owukira: Nthawi yotenthetsera kuyambira 150 ° C kupita kumalo osungunuka a aloyi imadziwikanso kuti nthawi yonyowa, zomwe zikutanthauza kuti flux ikuyamba kugwira ntchito ndikuchotsa cholowa m'malo mwachitsulo pamwamba pazitsulo kotero ndikukonzekera kupanga cholumikizira chabwino cha solder. pakati pa zikhomo ndi ma PCB.
3. Reflow zone: Reflow zone, yomwe imatchedwanso "time above liquidus" (TAL), ndi gawo la ndondomeko yomwe kutentha kwapamwamba kumafikira.Kutentha kwapamwamba kwambiri ndi 20-40 ° C pamwamba pa liquidus.
4. Malo ozizira: M'malo ozizira, kutentha kumachepera pang'onopang'ono ndikupanga zolumikizira zolimba.Kutsetsereka kwakukulu kololedwa kozizira kumafunika kuganiziridwa kuti pasakhale vuto lililonse.Kuzizira kwa 4°C/s ndikovomerezeka.

Pali mitundu iwiri yosiyana yomwe ikukhudzidwa ndi njira yobwereranso - mtundu wamadzimadzi ndi mtundu wa slumping.

Mtundu wa Soaking ndi wofanana ndi mawonekedwe a trapezoidal pomwe mtundu wa slumping uli ndi mawonekedwe a delta.Ngati bolodi ndi losavuta ndipo palibe zigawo zovuta monga BGAs kapena zigawo zikuluzikulu pa bolodi, slumping mtundu mbiri adzakhala kusankha bwino.