S2-Glass/Epoxy Unidirectional (MIL-HDBK-17)

Verifiedcomposite
· S2-Glass/Epoxy UD· S-2/Epoxy

S-2 Glass/Epoxy unidirectional composite is a fiber-reinforced polymer consisting of high-strength S-2 glass fibers (a boron-containing variant offering improved performance over standard E-glass) embedded in an epoxy matrix, processed via autoclave prepreg for consistent quality and fiber alignment. This material is widely specified in aerospace, defense, and marine structures where the unidirectional fiber orientation maximizes load-bearing capacity along the primary stress axis, making it a workhorse for damage-tolerant primary structures that require both strength and repeatability per military specifications. Engineers select S-2 Glass/Epoxy over E-glass alternatives when thermal performance and fatigue resistance justify the higher material cost, and over carbon-fiber systems when cost, impact tolerance, or electromagnetic transparency are design drivers.

helicopter rotor bladesaircraft fuselage and wing skinsmarine vessel hullsmissile radomesstructural repair patchesdefense ground equipment

Compliance & Regulations

?Conflict Free?FDA?RoHS?REACH?TSCA?Prop 65
PropertyValueUnitConditionsSource
Compressive Strength(σc)
ksiL
Poisson's Ratio(ν)
-notes
Shear Modulus(G)
ksinotes
Ultimate Tensile Strength(σUTS)
ksiL
Young's Modulus(E)
ksiL
Verified Unverified Low confidence (<80%) Link to source
PropertyValueUnitConditionsSource
Density(ρ)
lb/in³
Verified Unverified Low confidence (<80%) Link to source

Regulatory Screening

Environmental

Safety & Biocompatibility

Quality & Standards

RoHS, REACH, and Prop 65 statuses are validated against official substance lists (ECHA SVHC Candidate List, OEHHA Prop 65, RoHS Annex II). Other regulations are estimated from composition and material classification. All screening is a starting point for due diligence — always verify with your supplier before making compliance decisions.