Surface integrity after pickling and anodization of Ti–6Al–4V titanium alloy

Eric Vermesse (1, 2) , Catherine Mabru (1) , Laurent Arurault (2)

1 ICA - Institut Clément Ader
2 CIRIMAT - Centre interuniversitaire de recherche et d'ingenierie des matériaux

The surface integrity of Ti–6Al–4V titanium alloy was studied at different stages of surface treatments, especially pickling and compact anodization, through surface characteristics potentially worsening fatigue resistance. No significant changes of the equiaxe microstructure were detected between sample core and surface, or after the pickling and anodization steps. Surface hydrogen and oxygen superficial contents were found to remain unchanged. Roughness characteristics (i.e. Ra, Rz but also local Kt factor) similarly showed only slight modifications, although SPM and SEM revealed certain random local surface defaults, i.e. pits about 400 nm in depth. Finally internal stresses, evaluated using X-ray diffraction, highlighted a significant decrease of the compressive internal stresses, potentially detrimental for fatigue resistance.

Mots clés: Titanium alloy; Pickling; Anodization; Roughness; Internal stresses

Domaines: Matériaux; Matériaux

Eric Vermesse, Catherine Mabru, Laurent Arurault. Surface integrity after pickling and anodization of Ti–6Al–4V titanium alloy. Applied Surface Science, 2013, vol. 285 (Part B), pp. 629-637. ⟨10.1016/j.apsusc.2013.08.103⟩. ⟨hal-01150411⟩