标签: fr-4

FR-4是什么 铜箔基板的定义 FR-4之定义出自NEMA规范:LI1-1983, 指玻纤环氧树脂的试烧样本, 其尺寸为5吋长, 0.5吋宽, 厚度不拘的无铜基板, 以特定的本生灯, 在样本斜放45度的试烧下将其点燃, 随即移开火源而让已加有耐燃剂(如20%的溴)的板材自行熄灭, 并以码表记下离火后的 “延烧” 的秒数. 经过十次试烧后其总延烧的秒数低于50秒者称为V-0, 低于250秒者称为V-1. 凡合乎V-1的玻纤环氧树脂板材, 皆称为FR-4。 PCB除了常用的FR-4材质外, 其它还有高功能高Tg树脂, 如: BT, Polymide, Cyanate Ester及PTFE等. 但是FR-4的低价位, 良好接着力, 低吸湿性等优点是其它树脂所比不上的, 因此大部分的PCB都是使用FR-4材质制作。 铜箔基板（Copper-clad Laminate）简称CCL，为PC板的重要机构组件。它是由铜箔（皮） 、树脂（肉） 、 补强材料（骨骼)、及其它功能补强添加物（组织）组成。   PC板种类层数 应用领域 纸质酚醛树脂单、双面板 (FR1＆FR2) 电视、显示器、电源供应器、音响、复印机、录放机、计算器、电话机、游乐器、键盘 环氧树脂复合基材单、双面板 (CEM1CEM3) 电视、显示器、电源供应器、高级音响、电话机、游乐器、汽车用电子产品、鼠标、电子记事本 玻纤布环氧树脂单、双面板 (FR4 ) 适配卡、计算机外设设备、通讯设备、无线电话机、手表、游乐器 玻纤布环氧树脂多层板 (FR4 FR5) 桌上型计算机、笔记型计算机、掌上型计算机、硬盘机、文书处理机、呼叫器、行动电话、IC卡、数字电视音响、传真机、汽车工业、军用设备

We are all aware of printed circuit board material, also known asPC board, PCB, printed wiring board, or PWB. The last two names, though, don't seem to have caught on in the engineer's lexicon, despite the efforts of various standards bodies such as IPC which began in 1957 as the Institute for Printed Circuits but has since changed its name. The most common type is FR-4, with glass-epoxy substrate (see here ), but there are other materials available, such as low-cost, easily punchable phenolic as well as sophisticated, RF-optimized types. You can get FR-4-based PCB material in many sizes and standard types: unclad; copper-clad on one side; clad on both sides; with heavier cladding; and even with a pre-drilled, closely spaced array of holes. It's a strong, stiff, hard-to cut, tool-dulling, and very useful material which engineers use in many product roles besides its primary purpose of provide real estate and interconnect circuits, of course. For example, it's a quick and effective way to build a shielded box around a sensitive sub-circuit, since you can quickly solder the edges and get very good RFI/EMI attenuation. Or you can use it as an "above the board" third dimension to bring both power and ground (aka signal common) to parts of a circuit which need lower IR drop in a supply rail, or lower ground impedance. But the real beauty of this PCB material is its many non-circuit uses. I once cut a piece in a large, skinny "U" shape to be an internal stiffener within the floppy leather handle of a well-worn, classic briefcase. Another time, I laminated some to a plastic shelf which had cracked to poor design and material; the hole pattern in the PCB material acted as a "grab zone" for the epoxy adhesive and really made for a solid joining of the two layers. Among the other interesting uses is as a structural base for hand-building of model railroad turnouts (sometimes but erroneously called "switches"). The board comes etched with a tie pattern, to which the modeler solders the rails; the PCB forms a rigid yet thin base. You can also buy individual model-railroad ties for the same purpose, see here . (Of course, the modeler also has to cut a small gap in the ties using a cutoff wheel, or he'll have the kind of "rail-to-rail" performance which shorts the current-carrying rails. ;-) There are other examples; these are just a few that come to mind. What have you used PBC material for, besides electronic circuits and functional support? Have you ever used it to do an emergency repair, or as a structural element in a clever project design? I'm always interested in how people adopt and adapt basic items to solve problems for which they weren't originally intended or developed—that's a large part of the creativity and innovation process.

We all know printed circuit board material, also called PC board, PCB, printed wiring board, or PWB. The last two, however, don't seem to have caught on in the engineer's lexicon, despite the efforts of various standards bodies such as IPC which began in 1957 as the Institute for Printed Circuits but has since changed its name. The most common type is FR-4, with glass-epoxy substrate (see here ), but there are other materials available, such as low-cost, easily punchable phenolic as well as sophisticated, RF-optimized types. You can get FR-4-based PCB material in many sizes and standard types: unclad; copper-clad on one side; clad on both sides; with heavier cladding; and even with a pre-drilled, closely spaced array of holes. It's a strong, stiff, hard-to cut, tool-dulling, and very useful material which engineers use in many product roles besides its primary purpose of provide real estate and interconnect circuits, of course. For example, it's a quick and effective way to build a shielded box around a sensitive sub-circuit, since you can quickly solder the edges and get very good RFI/EMI attenuation. Or you can use it as an "above the board" third dimension to bring both power and ground (aka signal common) to parts of a circuit which need lower IR drop in a supply rail, or lower ground impedance. But the real beauty of this PCB material is its many non-circuit uses. I once cut a piece in a large, skinny "U" shape to be an internal stiffener within the floppy leather handle of a well-worn, classic briefcase. Another time, I laminated some to a plastic shelf which had cracked to poor design and material; the hole pattern in the PCB material acted as a "grab zone" for the epoxy adhesive and really made for a solid joining of the two layers. Among the other interesting uses is as a structural base for hand-building of model railroad turnouts (sometimes but erroneously called "switches"). The board comes etched with a tie pattern, to which the modeler solders the rails; the PCB forms a rigid yet thin base. You can also buy individual model-railroad ties for the same purpose, see here . (Of course, the modeler also has to cut a small gap in the ties using a cutoff wheel, or he'll have the kind of "rail-to-rail" performance which shorts the current-carrying rails. ;-) There are other examples; these are just a few that come to mind. What have you used PBC material for, besides electronic circuits and functional support? Have you ever used it to do an emergency repair, or as a structural element in a clever project design? I'm always interested in how people adopt and adapt basic items to solve problems for which they weren't originally intended or developed—that's a large part of the creativity and innovation process.