Carbon nanotubes: New composite materials

New composite materials can be used in ultra-efficient motors.

Scientists at the Oak Ridge National Laboratory in the United States have created a copper/carbon nanotube composite material that is 10 centimeters long and 4 centimeters wide using a new technique. The material can increase the current capacity of copper wire and can be scaled, which is a new material for ultra-efficient, high power density motors.

Carbon nanotubes are reported to be light, strong and highly conductive, so adding them to copper substrates to improve electrical conductivity and mechanical properties is not a new idea.

However, in the past research results, the composite material length is very short, only micron or millimeter scale, limited scalability, or its length is long but poor performance.

In this study, the scientists deposited and arranged carbon nanotubes on a flat copper substrate, resulting in a metal-based composite material with better current handling and mechanical properties than copper alone.

The researchers then coated the top of the carbon nanotubes with a thin copper film using magnetron sputtering, a vacuum coating technique, and annealed the sample in a vacuum furnace to form a dense, uniform copper layer, resulting in a highly conductive copper/carbon nanotube network.

The results show that the current capacity of the composite is improved by 14% and the mechanical properties are improved by 20%.

The research aims to promote the widespread use of electric vehicles in many ways, such as reducing costs and improving or extending the performance and life of electric motors and electronic components.

The material can be used in any component that uses copper, including more efficient busbars and smaller connectors for electric car traction inverters, as well as wireless and wired charging systems.