Pasinei ne laminated chimiro che multilayer pcb, chigadzirwa chekupedzisira chimiro chelaminated chemhangura foil uye dielectric. Zvinhu zvinokanganisa mashandiro edunhu uye mashandiro ekuita zvinonyanya kuita dielectric zvinhu. Naizvozvo, sarudzo yePCB board inonyanya kusarudza dielectric zvinhu, zvinosanganisira prepregs uye core board. Saka chii chinofanira kutariswa pakusarudza?

1. Girazi shanduko yekushisa (Tg)

Tg inzvimbo yakasarudzika yemapolymers, tembiricha yakakosha inosarudza zvinhu zvemukati, uye yakakosha parameter yekusarudza substrate zvinhu. Iyo tembiricha yePCB inodarika Tg, uye thermal yekuwedzera coefficient inova yakakura.

Zvinoenderana neTg tembiricha, mabhodhi ePCB anowanzo kukamurwa kuita yakaderera Tg, yepakati Tg uye yakakwirira Tg mabhodhi. Muindasitiri, mabhodhi ane Tg akatenderedza 135 ° C anowanzo kurongerwa seyakaderera-Tg mabhodhi; mapuranga ane Tg akapoteredza 150 ° C anorondedzerwa sepakati-Tg mabhodhi; uye mapuranga ane Tg akatenderedza 170 ° C anorongedzerwa seakakwira-Tg mabhodhi.

Kana paine nguva zhinji dzekutsikirira panguva yePCB processing (kupfuura 1 nguva), kana paine akawanda PCB layers (anopfuura gumi nemana akaturikidzana), kana solder tembiricha yakakwira (>14 ℃), kana tembiricha yekushanda yakakwira (kupfuura 230 ℃), kana solder thermal stress yakakura (Senge wave soldering), high Tg plates inofanira kusarudzwa.

2. Coefficient of Thermal Expansion (CTE)

Iyo coefficient yekuwedzera kwekupisa inoenderana nekuvimbika kwewelding uye kushandiswa. Nheyo yekusarudza ndeyekuenderana neiyo yekuwedzera coefficient yeCu sezvinobvira kudzikisa thermal deformation (dynamic deformation) panguva welding).

3. Kupisa kupisa

Kupisa kupisa kunonyanya kutarisisa kugona kutsungirira tembiricha yekudziya uye huwandu hwenguva dzekutengesa. Kazhinji, iwo chaiwo welding bvunzo inoitwa ine zvishoma kuomarara maitiro mamiriro pane yakajairika welding. Inogonawo kusarudzwa maererano nezviratidzo zvekushanda zvakadai seTd (kupisa pa 5% kuora kurasikirwa panguva yekupisa), T260, uye T288 (nguva yekupisa inopisa).