تشمل عناصر الهالوجين في الجدول الدوري للعناصر الكيميائية الفلور (ف), الكلور (كل), البروم (ر), اليود (أنا) and astatine (At). They exist in nature as typical of salts. “FR” means flame retardant. “4” represents a category of reinforced sheet materials, i.e., the fiberglass substrata. Halogen-free FR-4 can simply be regarded as an improved non-halogen product reinforced with the properties of flame retardance.
ما هو FR-4 الخالي من الهالوجين?
04
يناير