Bonding of Titanium Alloys

Surface pretreatments affect joint strength, some improve it, e.g. etching in aqueous hydrofluoric acid or oxidation in alkaline hydrogen peroxide; while others decrease the strength e.g. etching in acids containing high concentrations of oxidising agents.

For Ti-6A1-4V alloy, best results are obtained by either etching in aqueous hydrofluoric acid or oxidation in alkaline hydrogen peroxide for about two hours.

The results indicate that a pretreatment which leaves a coherent TiO₂-rutile layer, on a rough surface, form the strongest joints. Surface roughness is shown to enhance bond strength.