Umenzi wePCB okhuphisanayo

Xa ubushushu bebhodi yesekethe ye-Tg ephakamileyo buphakama kummandla othile, i-substrate iya kutshintsha ukusuka "kwi-glass state" ukuya kwi "rubber state", kwaye iqondo lokushisa ngeli xesha libizwa ngokuba yi-glass transition temperature (Tg) yeplate.Ngamanye amazwi, i-Tg lelona qondo lobushushu liphezulu (℃) apho i-substrate ihlala iqinile.Oko kukuthi, izinto eziqhelekileyo ze-substrate ze-PCB kubushushu obuphezulu azivelisi kuphela ukuthambisa, ukuguqulwa, ukunyibilika kunye nezinye izinto, kodwa kubonisa ukwehla okubukhali kwiipropati zoomatshini kunye nombane (Andiqondi ukuba ufuna ukubona iimveliso zabo zivela kweli tyala. ).

Iipleyiti ze-Tg ngokubanzi zingaphezu kwe-130 degrees, i-Tg ephakamileyo idla ngokungaphezulu kwe-170 degrees, kwaye i-Tg ephakathi imalunga ne-150 degrees.

Ngesiqhelo, i-PCB ene-Tg≥170℃ ibizwa ngokuba yibhodi yesekethe ye-Tg ephezulu.

I-Tg ye-substrate iyanda, kunye nokumelana nokushisa, ukunyanzeliswa komswakama, ukuchasana kweekhemikhali, ukuxhathisa ukuzinza kunye nezinye iimpawu zebhodi yesiphaluka ziya kuphuculwa kwaye ziphuculwe.Ukuphakama kwexabiso le-TG, ngcono ukusebenza kokumelana nobushushu bepleyiti kuya kuba.Ngokukodwa kwinkqubo engenalo i-lead, i-TG ephezulu ihlala isetyenziswa.

I-Tg ephezulu ibhekisela ekuxhathiseni ukushisa okuphezulu.Ngophuhliso olukhawulezayo lweshishini lombane, ngakumbi iimveliso zombane ezimelwe ziikhompyuter, ngokubhekiselele kuphuhliso lomsebenzi ophezulu, i-multilayer ephezulu, imfuno ye-PCB substrate imathiriyeli ephezulu yokumelana nobushushu njengesiqinisekiso esibalulekileyo.Ukuvela kunye nophuhliso lobuchwepheshe bofakelo loxinaniso oluphezulu olumelwe yi-SMT kunye ne-CMT yenza i-PCB ixhomekeke ngakumbi kwinkxaso yokumelana nobushushu obuphezulu be-substrate ngokubhekiselele kwi-aperture encinci, i-wiring emihle kunye nohlobo oluncinci.

Ke ngoko, umahluko phakathi kwe-FR-4 eqhelekileyo kunye ne-high-TG FR-4 kukuba kwimeko ye-thermal, ngakumbi emva kwe-hygroscopic kunye nobushushu, amandla omatshini, ukuzinza komgangatho, ukunamathela, ukufunxwa kwamanzi, ukubola kwe-thermal, ukwandiswa kwe-thermal kunye nezinye iimeko. izixhobo zahlukile.Iimveliso ze-Tg eziphakamileyo ngokucacileyo zingcono kunezixhobo eziqhelekileyo ze-PCB substrate.Kwiminyaka yakutshanje, inani labathengi abafuna ibhodi yesekethe yeTg ephezulu liye landa unyaka nonyaka.