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Removing oxide layer from NiTi wires

2003

I'm studying compatibility and adhesion between NiTi wire (152 - 201 microns) and epoxy matrix in order to realize a composite material that can damp vibration at low temperature. I founded problems due to the Ti oxide layer. Can you suggest any chemical or mechanical treatment?

Thank you for your time.

Carlotta Bertolini
Trento University - Trento, Italy

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2003

Are you sure that it is the oxide of Ti causing the problem. Nickel is the larger % of most of those alloys. In either case, it probably can be removed with 40% nitric acid, 1.5 % hydrofluoric acid and balance DI grade water.

Ammonium bifluoride can be used in place of the nasty HF and is far safer. About 1Lb/gal if I remember correctly. Rinse extremely well in DI water and store in a nitrogen environment as it will reoxidize amazingly fast.

James Watts
- Navarre, Florida