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Nitinol Parts Soldering

I understand that it is possible to solder nitinol parts using a Tin-Aluminium Solder but I need the exact composition of the solder in order to create a sustainable bond. Can anyone help?

Robyn Reilly
- Galway, Ireland

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Hi Robyn,

You can solder Nitinol using Sn-3.5% Ag solder and a suitable flux paste (something highly aggressive to dissolve the Ti02 surface). Using "Indalloy flux number 3" (active ingredient is HF) and "Indally solder number 121" (tin+3.5% silver) has been shown to work, but I think it is patented in Europe by Memory-metalle GmbH. You need to "fry" the nitinol in the flux and then add the solder - it can be tricky! Don't forget to wash the joint with water afterwards or it will corrode.

Paul Shutt
- Newcastle, UK