High strain rate effects on mechanical properties of inductively coupled plasma treated carbon nanotube reinforced epoxy composites

Abstract

Structures can be loaded statically or dynamically with a wide range of strain rate. With high strain rates, the relationship between stress and strain is not the same as that in static loading. It has been observed that polymer composite properties are dependent upon the strain rate at which they are tested. The most commonly used method for determining the dynamic response of materials is the Split Hopkinson pressure bar test, which can test materials at strain rates as high as 1200/s to 4200/s. It is observed that the compressive strength of thermoset epoxy resin increases up to 107% at a high stain rate compared with that at quasi-static loading. This shows strongly sensitive compressive behavior at high strain rates; i.e. the structural properties of the reinforcement and energy absorption capacity are affected at high strain rates. Reinforcing nitrogen doped multi-walled carbon nanotubes (MWCNTs) can effectively improve the compressive strength as well as the strain energy of the epoxy matrix due to their uniform dispersion in the epoxy matrix.