Boron/epoxy (B4/5505) UD lamina vs Kevlar 49/epoxy UD lamina

Every value below is a typical room-temperature figure with its source, test method and conditions — the same dataset that drives the calculators.

Boron/epoxy (B4/5505) UD lamina in fullKevlar 49/epoxy UD lamina in full← All materials
PropertyBoron/epoxy (B4/5505) UD laminaKevlar 49/epoxy UD laminaDifference
Density2 g/cm³1.38 g/cm³Boron/epoxy (B4/5505) UD lamina — 45% higher
E₁ (longitudinal)204 GPa80 GPaBoron/epoxy (B4/5505) UD lamina — 2.5× higher
E₂ (transverse)18.5 GPa5.5 GPaBoron/epoxy (B4/5505) UD lamina — 3.4× higher
G₁₂ (in-plane shear)5.59 GPa2.2 GPaBoron/epoxy (B4/5505) UD lamina — 2.5× higher
ν₁₂ (major Poisson)0.23 0.34 Kevlar 49/epoxy UD lamina — 48% higher
Xt (long. tension)1260 MPa1400 MPaKevlar 49/epoxy UD lamina — 11% higher
Xc (long. compression)2500 MPa235 MPaBoron/epoxy (B4/5505) UD lamina — 10.6× higher
Yt (transv. tension)61 MPa12 MPaBoron/epoxy (B4/5505) UD lamina — 5.1× higher
Yc (transv. compression)202 MPa53 MPaBoron/epoxy (B4/5505) UD lamina — 3.8× higher
S (in-plane shear)67 MPa34 MPaBoron/epoxy (B4/5505) UD lamina — 2.0× higher
  • Tsai & Hahn, Introduction to Composite Materials, 1980
  • Daniel & Ishai, Engineering Mechanics of Composite Materials, 2nd ed.

Typical room-temperature values for learning and preliminary design; grades vary widely and a supplier datasheet always overrides a textbook figure. Confirm against the datasheet before design work.