Uses of FR4 Sheets

FR4 Sheets is a popular material for circuit boards known by electrical engineers and people that are involved in the printing of circuit boards.  FR4 or FR-4 is the very backbone of the circuit board itself. It is often that yellow/greenish material that we are all familiar with. FR4 is what the circuit boards are printed on.  And, as a stiff fiber filled polymer, it is the perfect selection of circuit board printing.

What is FR4

FR4 Sheets

The FR4 name is both a rating and a name.  FR stands for flame retardant and the 4 is the class.  The fiberglass found in the material is finely woven to give the material its high tensile strength and a lower coefficient of thermal expansion.  This glass fiber is the reason for most of the stability in this material. A low coefficient of thermal expansion means, when it is exposed to heat, it is less likely to change in size.  Many materials will contract and expand with heat, however, even a little bit can really damage a circuit board. This is why it is very important to use only materials with a low coefficient thermal expansion.  

FR4’s low coefficient of thermal expansion as well as its other properties makes it the perfect circuit board material.  This is a widely used material in the circuit board industry as well. And, this industry expands into the phone, radio, tv, computers and so many more industries that use circuit boards.  However, it can not only be found in the circuit board industry but is also popular in the marine industry. This material not only resists to shrinking and expansion, but it also resists water absorption.  Which is perfect for the marine industry.

FR4 Sheets Are Very Stable

FR4 also acts as a great insulator.  This property further makes it a great choice for circuit boards.  Circuit boards have a lot of electrical current running through them.  However, it can be machined as well. Machining FR4 makes great insert components in injection molding.  It cannot be molded by injection molding but can make a great insert because of its stability.

FR4 Sheets Uses

An even dielectric constant is important when making circuit boards as well.  FR4 is very stable and offers this property. It is important that the properties from one board to the other are consistent.  This consistency of the FR4 sheets allows all the electrical components of the circuit boards to be attached consistently. This is important as all those tiny components have a job and they all need to work together within the board.  If there is too much tolerance to the materials, the gaps will grow with time. These wide tolerances will cause all kinds of issues within the circuit boards.

FR4 Sheets have proven time and time again to be the perfect material for circuit board printing.  It’s stable properties, lack of water absorption and extremely high mechanical strength make it the perfect choice for circuit board printing.  And, that is exactly why we use it for just that!

If you have a circuit board application you are need of having manufacturers, give us a call.  We would be happy to discuss your options.