Crazing behaviour

Many epoxy composites are now incorporated into the design of jets, planes and other vehicles.

Composite materials are extremely lightweight, which lowers the overall weight of the vehicle and boosts fuel efficiency.

The downside is that epoxy composites can be brittle, which is detrimental to the vehicle’s structural integrity.

Now, a researcher at Rensselaer Polytechnic has demonstrated that incorporating chemically treated carbon nanotubes into an epoxy composite can significantly improve the overall toughness, fatigue resistance and durability of a composite frame.

When subjected to repetitive stress, a composite frame infused with treated nanotubes exhibited a five-fold reduction in crack growth-rate compared with a frame infused with untreated nanotubes; when compared with a composite frame made without nanotubes, it exhibited a 20-fold reduction.

This newfound toughness and crack resistance is a result of the treated nanotubes, which enhance the molecular mobility of the epoxy at the interface where the two materials touch.