The researchers observed that the cracked pieces of metal healed on their own without any human intervention. A new experiment left scientists shocked after the metal healed itself. Scientists at Sandia National Laboratories and Texas A&M University tested the metal’s durability, using a specialized transmission electron microscope technique to pull the ends of the metal 200 times per second, Science Alert reported.
A crack initially formed and spread. But after about 40 minutes of the experiment, the metal rejoined. The researchers called this treatment “cold welding”. The researchers observed the metal self-healing at ultra-small scales in a 40-nanometer-thick piece of platinum suspended in a vacuum.
Groundbreaking discovery could revolutionize engineering. The results of the experiment were published in the journal Nature. “The cold welding process is a metallurgical process known to occur when two relatively smooth and clean metal surfaces are brought together to reform atomic bonds,” said Brad Boyce, materials expert at Sandia National Laboratories.
“Unlike the self-repairing robots in the movie ‘Terminator,’ this process is not visible on a human scale. It occurs at the nanoscale, and we have yet to be able to control this process,” added Mr. Boyce.
The metal pieces were about 40 nanometers thick and several micrometers wide. While healing has only been seen in experiments with platinum and copper, Boyce said simulations have shown that self-healing can occur in other metals, and that it is “quite likely” that alloys such as steel could exhibit this quality. “It’s possible to imagine materials tailored to take advantage of this behavior,” Boyce said.
“Given these new findings, there may be alternative material design strategies or engineering approaches that could be designed to help mitigate fatigue failure. Additionally, this new understanding may shed light on fatigue failure in existing structures – improving our ability to interpret and predict such disturbances.” failure,” Boyce added.
Scientists have produced some self-healing materials in the past, mostly plastics. Study co-author Michael Demkowicz, professor of materials science and engineering at Texas A&M University, predicted the self-healing of the metal a decade ago.
Demkowicz correctly reasoned that under certain conditions, subjecting the metal to stresses that would normally exacerbate fatigue-related cracks could have the opposite effect. “I now estimate that it will take another 10 years to develop tangible applications of our findings,” Demkowicz said.
“When I first made my predictions, some in the press said I was working on the T-1000. That’s still science fiction,” Demkowicz said. “However, at the end of (the TV series) Battlestar Galactica, the crew modified some Cylon technology (a fictional robotic race) to help heal the fatigue damage to their ship, which made the metal act more like organic tissue that could heal itself. early. I’d say what we’re working on is more in line with the ‘Battlestar Galactica’ example.”
The self-healing was observed in a very specific environment using a device called an electron microscope. “One of the big questions the study left open is whether this process also happens in air, not just in the vacuum environment of a microscope. But even if it only happens in a vacuum, it still has important implications for fatigue in space vehicles.” or fatigue associated with subsurface cracks that are not exposed to the atmosphere,” Mr Boyce said.