Carbon Nanotubes Make Aluminum as Hard as Steel But One Third the Weight

The hardness of the composite aluminum and carbon nanotubes is several times greater than that of unalloyed aluminum, tensile strengths comparable to those of steel can be achieved, and the impact strength and thermal conductivity of the lightweight metal can be improved significantly.

High hardness levels and tensile strengths could only be achieved in aluminum by a complex alloying process based on rare and expensive metals.

“Our carbon nanotubes are an attractive alternative to such complicated alloys. Baytubes carbon nanotubes can also significantly reinforce aluminum materials already alloyed with metals,” says Adams.

The density of CNT-reinforced aluminum is only around one third that of steel. Therefore, the material can be used in any number of applications in which the goal is to reduce weight and energy consumption.

With its combination of high strength and low weight, Baytubes-reinforced aluminum is a welcome alternative to steel, expensive specialty metals such as titanium, and carbon-fiber-reinforced plastics.

“This new class of materials has great potential for the production, for example, of screws and other connecting elements, allowing existing manufacturing processes (stamping, CNC) to be retained. Lightweight, heavy-duty components for wheelchairs or athletic equipment are also ideal candidates for the material,” says Adams.

Baytubes-reinforced aluminum I-beams could conceivably be manufactured for the construction industry, because they are much lighter than steel I-beams, making it possible to construct taller buildings. Steel I-beams currently are a factor limiting the maximum height of a skyscraper, because of their inherent weight.

Promising applications exist too in the automotive and aircraft industries.