Breakthrough Discovery: Scientists Unveil Toughest Material Ever Found at 'Ultra-Cold' Temperatures

Researchers at the University of Bristol have reportedly discovered an alloy that increases strength at more than -250 degrees Celsius, which would make it the toughest material known to man.

According to a release published on the university website, the findings were published in Science and show that the chromium-cobalt-nickel alloy has a high fracture toughness in cryogenic temperatures. The material is set to be used in the world’s most extreme environments and also space. A phase transformation takes place that leads to the behavior exhibited when combined with other “nano-scale mechanisms, prevents crack formation and propagation.”

“This is very interesting because most alloys become more brittle with a decrease in temperature. I reference the sinking of liberty ships in WWII and Titanic which were due to the metals losing its ductility at low temperatures,” said lead author Dr Dong Liu of Bristol’s School of Physics. “People often mix the concept of strength and toughness. If you Google, ‘what is the toughest materials on earth?’ ‘Diamond’ will jump out on the top line. Diamond is the hardest known material to date, but hardness is usually related to strength of a material - diamond is indeed very hard and strong but it is not tough.”

The release adds that structures like nuclear pressure vessels need metals that are not as hard but can tolerate damage. The metals also give out a warning before breaking, which is a vital component.

“As this CrCoNi material does not decrease in strength and toughness as it becomes as cold as 20 Kelvin, it can be potentially used as structural or load-bearing components for many potential applications in space and cold regions on earth and other planets,” Dr Liu said. “Also, as we have discovered the mechanisms that are responsible for the improved strength and toughness. This means these processes can be used as a design guide for scientists and engineers to design better materials.”

Dr. Liu went on to say that the experimental testing of the toughness of the material, at 20K, is something that took years to design and complete. He said the success of the experiment was due to the experience and expertise of his team in testing materials in extreme conditions.

The team’s work is being considered groundbreaking, and Dr. Liu and the team are focused on exploring underlying mechanisms of the material and potential applications, while also providing insights for design of improved materials in other fields.