Engineers have developed a technology for restoring the structure of damaged foam metal using electroplating at room temperature.
For more than 6 thousand years, mankind has been using metals to make various things because of their strength and rigidity. It takes a lot of energy to damage them, but this also applies to the process of their recovery, which usually occurs by melting at a high temperature. but this repair method is not always applicable, for example, for metal foam with a complex internal structure.
Scientists from the University of Pennsylvania recently found a solution. To do this, they used chemical vapor deposition to uniformly coat each strut of nickel foam with a layer of parylene D, a chemically inert and elastic polymer. Since the resistance to damage of this material is slightly lower than that of nickel, it breaks faster, exposing the metal underneath. The researchers then used electroplating to form new nickel posts only on exposed metal where they were needed..
Ions easily move through the liquid electrolyte to the desired site, and using electrochemistry they are converted into a solid metal. The polymer acts like a lithographic mask and allows ions to be transformed into metal only at the point of damage. With this method, the team was able «heal up» specimens with cracks, partial breaks and broken in half.
Full recovery took about four hours, and since electroplating affects all exposed nickel, this time is independent of sample size..
Scientists compare the created foam metal with bone due to a similar regeneration mechanism. They also say that an electrolyte liquid can be placed inside a metal foam, and when broken, cover the rupture area, rebuilding the structure after an external voltage is applied..
This will allow for repairs without removing the damaged element, which is useful for transport, robotic equipment and spacecraft..
We also reported earlier that scientists have developed a technology for the production of ultra-light and very durable metal foams.
text: Ilya Bauer, photo: University of Pennsylvania
Welcome To Future