Indium Blog

Softness: Use Indium's Unique Property to Your Advantage

  • Indium

  • One of the most notable physical properties of pure indium is how soft it is. At many of the trade shows I have attended for Indium Corporation, we bring a rod or ingot of pure indium - simply because it is incredible for our visitors to handle a metal that is so soft. It’s not uncommon to see a smile from someone who has never handled indium before, as they bend a rod or ingot with their bare hands – a feat that would be unthinkable for common metals like steel or copper or aluminum.

    Indium metal is so soft that is easily bent, even at cryogenic temperatures.There are uncountable uses for a metal as soft as indium; one blog post could not do the topic justice. Let’s pick just one way you could use this property of indium to your advantage: sealing.

    Indium wire is a very common material for sealing applications. Indium wire is cut to length, formed into an o-ring, and then used as a seal. Because it is soft, the metal can flow in the seating groove and conform to any irregularities in the mating surfaces. This principle and property was used when NASA captured moon rock samples and returned them to Earth. They weren't sure what else they might be bringing home with them, so they decided to seal the entire sample hermetically, using indium, until they could open the samples in a secure environment.

    I’m sure you can come up with a handful of similar ideas for the use of a soft metal. If you need help using indium in your application, please let us know how we can help.

    This post is part of the “6 Strange Properties of Indium” series.

    Authored by previous Indium Application Manager Jim Hisert