Lapho izinga lokushisa lebhodi eliphrintiwe le-Tg eliphakeme likhuphukela endaweni ethile, i-substrate izoshintsha isuka "kwisimo sengilazi" ibe "isimo senjoloba", futhi izinga lokushisa ngalesi sikhathi libizwa ngokuthi izinga lokushisa lokuguqulwa kwengilazi (Tg) yebhodi.
Ngamanye amazwi, i-Tg izinga lokushisa eliphakeme kakhulu (°C) lapho i-substrate igcina ukuqina. Okusho ukuthi, izinto ezijwayelekile ze-PCB substrate azikhiqizi kuphela ukuthambisa, ukuguqulwa, ukuncibilika nezinye izinto emazingeni okushisa aphezulu, kodwa futhi zibonisa ukwehla okukhulu kwezici zemishini nezikagesi (ngicabanga ukuthi awufuni ukubona lokhu emikhiqizweni yakho) .
Ngokuvamile, amapuleti e-Tg angaphezu kuka-130 degrees, i-Tg ephakeme ivamise ukuba mkhulu kuno-170 degrees, kanti i-Tg ephakathi icishe ibe ngu-150 degrees. Ngokuvamile ibhodi eliphrintiwe le-PCB eline-Tg≥:170℃ libizwa ngebhodi eliphrintiwe le-Tg eliphezulu. I-Tg ye-substrate iyanda, futhi ukumelana nokushisa, ukumelana nomswakama, ukumelana namakhemikhali, ukuzinza kanye nezinye izici zebhodi eliphrintiwe kuzothuthukiswa futhi kuthuthukiswe. Ukuphakama kwevelu ye-TG, kuba ngcono ukumelana nezinga lokushisa kwebhodi, ikakhulukazi kunqubo engenamthofu, lapho izicelo eziphezulu ze-Tg zivame kakhulu. I-High Tg isho ukumelana nokushisa okuphezulu.
Ngokuthuthuka okusheshayo kwemboni ye-elekthronikhi, ikakhulukazi imikhiqizo ye-elekthronikhi emelwe amakhompyutha, ukuthuthukiswa kokusebenza okuphezulu kanye nama-multilayer aphezulu kudinga ukumelana nokushisa okuphezulu kwe-PCB substrate materials njengesiqinisekiso esibalulekile.
Ukuvela nokuthuthukiswa kobuchwepheshe bokukhweza obuphezulu obumelelwe i-SMT.CMT kwenze ama-PCB angakwazi ukuhlukaniswa kakhulu nokusekelwa kokumelana nokushisa okuphezulu kwama-substrates ngokuvula indawo encane, isifunda esihle kanye nokuncipha. Ngakho-ke, umehluko phakathi kwe-FR-4 evamile kanye ne-Tg FR-4 ephezulu: ingamandla emishini, ukuzinza kwe-dimensional, ukunamathela, ukumuncwa kwamanzi, nokubola okushisayo kwento ngaphansi kwesimo esishisayo, ikakhulukazi uma kushisa ngemva kokumuncwa komswakama. Kunomehluko ezimeni ezahlukahlukene njengokunwetshwa okushisayo, imikhiqizo ephezulu ye-Tg ngokusobala ingcono kunezinto ezijwayelekile ze-PCB substrate. Eminyakeni yakamuva, inani lamakhasimende adinga amabhodi aphrintiwe we-Tg aphezulu liye landa unyaka nonyaka.