Researchers in Canada have developed new nanostructured high entropy alloys with higher strength and stability at high temperatures compared to other metals, showing potential for use in industries including aerospace and automotive.
Engineers at the University of Toronto found that alloys made from nickel, iron, cobalt, tungsten and molybdenum could withstand temperatures up to 500°C, compared with 270ºC for pure nickel.
Nanostructured high entropy alloys – metals made from a chaotic mix of several different elements – have shown a lot of promise for use in industries such as aerospace and automotive because of their strength and stability at high temperatures compared with regular metals. But they are expensive and energy-intensive to produce.
The study found that by using Electrodeposition, which involves dissolving metal ions in water and using an electric current to pull them out of the liquid and form solid materials, is a cost-effective and lower energy way to create alloys.
They also discovered that alloys made with four different elements could withstand higher temperatures than those made with three, but adding a fifth element made no extra improvements – leaving it cheaper and easier to work with fewer elements, and allowing for efficiency when looking for new applications.
These alloys are anticipated to be useful for making tools or parts for applications where temperatures will be extremely high, “anywhere that we are trying to push materials to their absolute limits,” said University of Toronto materials engineer Michel Haché.
The research was sponsored by the Canadian Light Source, a national research facility which focuses on health, agriculture, and have been published in the international journal Surface and Coatings Technology.
