The material of
PCB circuit board can be divided into two categories: rigid base material and flexible substrate material. Copper clad laminate is an important material for rigid base materials. It is made of reinforcing Material, dipped in resin adhesive, dried, cut and stacked to form billet, then coated with copper foil, using steel plate as a mold, and processed by high temperature and high pressure forming in a hot press. Generally, the semi-solidified sheet used in multilayer laminates is the semi-finished product of copper clad laminates (mostly made of glass cloth immersed in resin and dried).
PCB circuit boards, or printed circuit boards, are the providers of electrical connections to electronic components. Its development has a history of more than 100 years; its design is mainly layout design; the main advantage of using circuit boards is to greatly reduce wiring and assembly errors, improve the level of automation and productivity. According to the number of PCB layers can be divided into single-panel, double-panel, four-layer board, six-layer board and other multi-layer PCB.
PCB PCB introduction: according to brand quality level, from bottom to height is as follows:
9 4 h B - 9 4 V - 22 F - cm - 1 - cm - 3 - 4 - 4
The detailed parameters and uses are as follows:
94HB: Ordinary cardboard, non-fireproof (minimum material, die punching, not power board) 94V0: flame retardant cardboard (die punching)
22F: single-sided fiberglass panel (die piercing)
CEM-1: single glass fiberboard (must be drilled by computer, not punched).
CEM-3: Double-sided semi-glass fiberboard (besides double-sided cardboard, which is the lowest end material for double-sided cardboard. Simple double-sided cardboard can be used with this material, 5-10 yuan / square meter cheaper than FR-4)
FR-4: double sided fiberglass panel
Flame retardancy
PCB circuit board raw material materials and parameters document download https://www.wendangxiazai.com/b-12a8dc66ddccda38376baf97.html grading can be divided into 94VO-V-1-V-2-94HB four semi-cured tablets: 1080 = 0.0712mm, 2116 = 0.1143mm, 7628 = 0.1778mm
FR4 CEM-3 is for board, FR4 is for fiberglass board, cem3 is for composite substrate halogen-free refers to the substrate does not contain halogen (fluorobromide iodine and other elements), because bromine is burning
When burning, it produces toxic gas and environmental protection requirements. Tg is the glass transition temperature, that is, melting point.
The circuit board must be flame resistant. It can not burn at a certain temperature and can only soften. The temperature point is called the glass transition temperature (Tg), which is related to the dimensional durability of the
PCB board.
