Why FR4 is used for PCB board ?

What is FR-4?

Fr4 Fiber Glass Epoxy Sheet which is the abbreviation of glass fiber cloth, is a kind of circuit board raw material and base material, the code name of flame-resistant material grade, which means that the resin material must be able to extinguish itself after burning. A material specification. Most commonly used in PCB (printed circuit board), general single-sided, double-sided and multi-layer PCB circuit boards are made of this! Because of its high strength and flame retardancy, most circuit boards will choose FR-4 as the base material.

2. What is a PCB and its composition?

PCB is the abbreviation of Printed Circuit Board in English. The Chinese name is printed circuit board, also known as printed circuit board and printed circuit board. It is an important electronic component. It is a provider of electrical connections for electronic components.

A PCB starts with the most basic unit: the substrate, which consists of several layers, each of which plays an important role in the functionality of the final PCB. These alternating layers include:

• Substrate: This is the base material of the PCB. It makes the PCB rigid.

• Copper: Add a thin layer of conductive copper foil to each functional side of the PCB - on one side if it is a single-sided PCB, or on both sides if it is a double-sided PCB. This is the copper trace layer.

• Solder mask: On top of the copper layers is the solder mask, which gives each PCB its characteristic green color. It brings copper traces into inadvertent contact with other conductive materials that could cause a short circuit. In other words, the solder keeps everything in place. The holes in the solder mask are where the solder is applied to connect the component to the board. Solder mask is a critical step for smooth PCBA manufacturing as it prevents soldering on unwanted parts and avoids short circuits.

• Silkscreen: The white silkscreen is the last layer on the PCB. This layer adds labels on the PCB in the form of characters and symbols. This helps give an indication of the function of each component on the board.

Advantages and characteristics of G10 Fr4 Insulate Sheet

General single-sided, double-sided and multi-layer PCB circuit boards are made of FR-4, FR in FR-4 means flame retardant, and the number 4 distinguishes the material from other materials in this category. FR-4 is a fiberglass reinforced epoxy laminate that looks like a thin woven cloth panel. The term FR-4 also stands for the grade used to make these laminates. The fiberglass structure provides structural stability to the material. Fiberglass layers are covered with flame retardant epoxy resin. This brings durability and strong mechanical properties to the material. All of these features make FR-4 printed circuit boards popular among electronic contract manufacturers.

Its technical features mainly lie in: electrical insulation, stable performance, good flatness, smooth surface, no pits, standard thickness tolerance, suitable for products that require high-performance electronic insulation, such as FPC reinforcement boards, PCB drilling backing boards , glass fiber meson, potentiometer carbon film printing glass fiber board, precision planetary gear (wafer grinding), precision test plate, electrical (electrical) equipment insulation stay partition, insulation backing plate, transformer insulation board, motor insulation parts, grinding Gears, electronic switch insulation boards, etc.

FR-4 sheet has been widely used in electronic products such as military industry, communication, computer, digital circuit, industrial instrumentation, automobile circuit, etc., and all performance indicators can meet the needs of general industrial electronic products. There is a very good price-performance ratio.

Example: Industrial battery circuit board

Plate type: FR-4