PCBA,Ukusetyenzwa kwe-SMT ngokubanzi kuneentlobo ezimbini zenkqubo, enye yinkqubo engenalothe, enye yinkqubo yokukhokela, sonke siyazi ukuba ilothe iyingozi ebantwini, ngoko ke inkqubo engenalothe iyahlangabezana neemfuno zokhuseleko lokusingqongileyo, ngumkhwa we amaxesha, ukhetho olungenakuphepheka lwembali.
Apha ngezantsi, umahluko phakathi kwenkqubo yokukhokela kunye nenkqubo engahlawulelwayo ishwankathelwa ngokufutshane ngolu hlobo lulandelayo.Ukuba ubuchwephesha behlabathi jikelele uhlalutyo lwe-chip ye-SMT alugqibekanga, siyathemba ukuba ungenza izilungiso ezingakumbi.
1. Ukubunjwa kwe-alloy kuhluke: i-63 / 37 ye-tin kunye ne-lead ixhaphake kwinkqubo yokukhokela, ngelixa i-sac 305 i-alloy-free alloy, oko kukuthi, SN: 96.5%, Ag: 3%, Cu: 0.5% .Inkqubo yasimahla yokukhokela ayinakuqinisekisa ngokupheleleyo ukuba akukho lead kwaphela, iqulethe kuphela umxholo ophantsi kakhulu welothe, njengelothe engaphantsi kwe-500 ppm.
2. Amanqaku okunyibilika ahlukile: indawo yokunyibilika yetoti yi-180 ° ukuya kwi-185 ° kunye nobushushu bokusebenza bumalunga ne-240 ° ukuya kuma-250 °.Indawo yokunyibilika yetoti engenalothe yi-210 ° ukuya ku-235 ° kwaye ubushushu obusebenzayo yi-245 ° ukuya ku-280 ° ngokulandelelanayo.Ngokwamava, yonke i-8% - i-10% inyuka kumxholo we-tin, indawo yokuncibilika iyanda malunga nama-degrees angama-10, kwaye ukushisa okusebenzayo kwandisa ngama-10-20 degrees.
3. Iindleko zihluke: i-tin ibiza kakhulu kunelothe, kwaye xa utshintsho olubalulekileyo lwe-solder lukhokelela kwi-tin, ixabiso le-solder linyuka kakhulu.Ngoko ke, iindleko zenkqubo yokungafumani ilothe iphezulu kakhulu kunenkqubo yokukhokela.Ubalo lubonisa ukuba iindleko zenkqubo yokukhokela i-lead-free ngamaxesha angama-2.7 aphezulu kunenkqubo ye-lead-free, kunye neendleko ze-solder paste ye-reflow soldering malunga namaxesha angama-1.5 aphezulu kunenkqubo yokukhokela.
4. Inkqubo ihluke: kukho iinkqubo ezikhokelayo kunye ne-lead-free, ezinokubonwa kwigama.Kodwa ezithile kwinkqubo, oko kukuthi ukusebenzisa solder, amacandelo kunye nezixhobo, ezifana amaza solders eziko, solder umatshini wokushicilela paste intlama, isinyithi soldering for ukuwelda manual, njl. Oku kwakhona esona sizathu siphambili kutheni kunzima ukuba inkqubo zombini lead- iinkqubo ezikhululekileyo nezikhokelayo kwindawo encinci yokusetyenzwa kwePCBA.
Umahluko kwezinye iinkalo, ezifana nenkqubo yefestile, i-weldability kunye neemfuno zokukhuselwa kwendalo nazo zahlukile.Ifestile yenkqubo yenkqubo yokukhokela inkulu kwaye i-solderability ingcono.Nangona kunjalo, ngenxa yokuba inkqubo yokungabikho kwe-load ihambelana ngakumbi neemfuno zokusingqongileyo, kunye nenkqubela phambili eqhubekayo yeteknoloji nangaliphi na ixesha, iteknoloji yenkqubo ye-lead-free iye yathembeka ngakumbi kwaye ikhulile.
Ixesha lokuposa: Jul-29-2020
