This glass/epoxy laminate offers a superior strength/size ratio in addition to its self-extinguishing properties. In addition to its high mechanical strength, it exhibits good dielectric loss and electrical strength under a range of dry and humid conditions. The flame resistance is Class I in accordance with NEMA test method 7.11.
A History of G-10 and FR-4
G-10 is a thermosetting industrial laminated plastic consisting of a woven glass cloth material and an epoxy resin matrix. First introduced in the 1950’s, G-10 was the original glass of epoxy laminate used in printed circuitry. The high strength, excellent electrical properties, and chemical resistance of G-10 make for a very versatile material that is now being used in a wide variety of applications.
Today most of what is called G-10 is actually FR-4, the flame retardant version of G-10. This explains why you will also see the material designated G-10FR. This means FR-4. The material FR-4 can usually be used where G-10 is called out, however, G-10 should not be used where FR-4 is specified.
G-10 and FR-4 can be fabricated using standard machine tools. However, it should be recognized that these materials require modifications from the machining of metals or thermoplastics. Their lower shearing strength permits higher speeds and feeds, and greater clearances and less rake on cutting tools is required.
It must also be recognized that certain machining operations, such as drilling parallel with the laminations or milling at right angles to the laminations, will require additional care due to the laminated structure. In all machining operations on these materials it is extremely important to keep tools sharp.
The mechanical and electrical properties of G-10 AND FR-4 are excellent and very similar, the flame retardant characteristic of FR-4 being the most obvious difference.
G-10 and FR-4 are rated at 140 degrees C (284 degrees F) continuous operating temperature. Being thermosets, no melting will occur with these grades; however, charring will be observed after extended periods above the temperature rating. FR-4 has flammability rating of 94V-0.
G-10 is also one of the most widely used non-metallics in cryogenic applications. This material should be noted as G-10CR and component specification should be reviewed before calling out.
G-10 and FR-4 laminates come in sheet, tube, and rod forms. They are also made in special shapes depending on the availability of tooling.
Colors that G-10/FR4 is available in upon request