G10 vs FR4              

The question “What is the difference between NEMA grade G-10 (Mil-I-24768/2 Type GEE) and NEMA Grade FR4 (Mil-I-24768/27 Type GEE-F)?” is commonplace in the composite industry. Although they are typically made from the same base material (E-Glass), the epoxy resin matrix used for binding each material is inherently different. This is due to the addition of trace amounts of a bromine compound into the resin matrix for FR-4. “FR’ stands for flame retardant, and indicates that the flammability of FR-4 is in compliance with the UL standard 94V-0. The Mil-I-24768 & NEMA specs require similar mechanical and electrical properties for both material grades. However, modern FR-4 resins and manufacturing processes produce superior mechanical and electrical properties compared to G-10. One area where G-10 will actually outperform the FR-4 is when the material application is immersed in salt water.  For more information on Lamitex grade composites please visit our page data.