Kev xaiv cov khoom siv yog ua raws li kev ntsuam xyuas dav dav ntawm kev ua tau zoo, cov khoom siv yuav tsum tau ua, thiab cov yam ntxwv ntawm lub zog. Cov nqi hluav taws xob sib txuas sib txawv nyob ntawm tus nqi ntawm cov khoom siv, kev ua haujlwm nyuaj, thiab kev ua haujlwm ntau lawm. Cov ntaub ntawv tseem ceeb muaj xws li insulators (yas resins) thiab conductors (phosphor bronze, tooj dag). Cov khoom siv hluav taws xob uas siv rau cov khoom siv hluav taws xob xws li LCP, Nylon, thiab PBT.
LCP
Tus cwj pwm los ntawm qhov tsis tshua muaj coefficient ntawm kev nthuav dav, tsis tshua muaj kev txhaj tshuaj molding shrinkage, tshwj xeeb lub zog thiab elastic modulus, thiab kub tsis kam (nrog kub deflection kub txog li 340 degree). Nws kuj muaj cov tshuaj tiv thaiv zoo heev thiab airtightness. Yog li ntawd, LCP yog cov khoom nyiam rau cov khoom sib txuas-tshwj xeeb tshaj yog cov uas xav tau SMT kev sib raug zoo- xws li Mini PCI Express thiab DDR connectors.
Nylon
Muab cov nqi qis dua, siab tensile zog, zoo heev hnav tsis kam, thiab tus kheej -lubricating zog. Nws zoo flowability yooj yim nyias -phab ntsa molding; Txawm li cas los xij, nws nthuav tawm qhov shrinkage tseem ceeb thiab nyiam tsim flash. nruj me ntsis ua ntej- molding kom qhuav yuav tsum tau tiv thaiv hydrolysis. Nylon feem ntau yog siv rau cov khoom sib txuas, tshwj xeeb tshaj yog hom DIP, xws li PCI 120P thiab PCI Express.
PBT
Cov yam ntxwv ntawm tus nqi qis, siab zog, thiab kev sib txhuam zoo. Txawm li cas los xij, nws muaj qhov tsis zoo moldability thiab tseem ceeb shrinkage. Vim nws qhov qis melting point, cov yas yuav yaj thaum lub sij hawm yoj soldering txheej txheem.
