G10 material is a woven-fiberglass/epoxy thermoset laminate classified under NEMA LI-1 Grade G-10. It belongs to the glass epoxy family — composites made from woven glass cloth impregnated with epoxy resin and cured under heat and pressure into rigid sheet, rod, and tube stock. G10 is the non-flame-retardant baseline of the family and is valued for its excellent strength-to-weight ratio, dimensional stability, and reliable dielectric performance across a wide range of industrial and structural applications.
G10 material delivers 40,000 psi tensile strength, 75,000 psi flexural strength, and a notably high 65,000 psi compressive strength. Water absorption over 24 hours is only 0.11% — keeping dimensional changes minimal in humid or immersed environments. Maximum continuous service temperature is 280°F (140°C). G10 plastic is rated UL 94HB. Available as g10 sheet and g10 rod, it is widely specified for terminal boards, structural spacers, insulating barriers, jigs, fixtures, and precision-machined parts. The g10 fiberglass sheet format is particularly common for cut-to-size electrical insulation work.
Standards. G10 meets NEMA LI-1 Grade G-10 and is tested per ASTM D709 for laminated thermosetting materials. It is not flame retardant (94HB rated) — applications requiring a flame-rated variant should specify NEMA g10-equivalent grade FR-4 instead.
Grade comparisons. Choose FR-4 when UL 94 V-0 flame retardance is required — it shares a similar property profile with the addition of flame-retardant additives. Step up to G-11 when continuous service temperatures exceed 140°C or when higher flexural retention at temperature is needed. For flame-retardant high-temperature service, see FR-5. Ready Plastics stocks G10 sheet and rod — request a datasheet for dimensions and tolerances.
