Epoxy resins and their composites are characterized by high stiffness, good chemical resistance and excellent fatigue performance. However, their high cross-linking density makes them brittle. In order to improve the overall mechanical performance of epoxy resins, various fillers, such as silica nanocomposites, can be added. Because of the good combination of mechanical properties, epoxy resins are widely used as matrix material for high-performance composites in aeronautical applications. Such structures are often subjected to impact events, such as bird strike or fan blade out. Therefore, the investigation of the effect of strain rate on the mechanical behaviour of the epoxy resin and its composites is necessary.

DyMaLab has been involved in studies where the effect of silica filler content and strain rate on the compressive behaviour of epoxy resin was investigated. The following findings were obtained on the material:

• Both neat and nanoparticle filled epoxy resins are strain rate-sensitive in compression, with an increase in strength with increasing strain rate.
• The addition of silica nanoparticles improves the compressive strength of the epoxy resin at all strain rates.
• The filler size and surface functionalization do not affect the resin compressive behavior at different strain rates.