In this study

the adhesion properties of titanium alloy after three different surface treatments

i.e.

acid wash

sulfuric acid anodizing and micro-arc oxidation

were investigated by tensile shear tests based on plateplate specimens. The control sample (without any surface treatment) exhibits a shear strength of 30.1MPa and features an adhesion failure. The acid wash sample shows a shear strength of 45.3MPa

half adhesion failure and half cohesive failure. The anodized sample possesses the optimal shear strength of 61.6MPa

and shows cohesive failure. But the microarc oxidation sample only has a shear strength of 9MPa and fails in intermediate tear of the oxide film layer. The results indicate that both acid wash and sulfuric acid anodizing can improve the adhesion properties

whereas micro-arc oxidation treatment cannot. In the case of anodizing in sulfuric acid

abundant micro rough structures are formed and generating higher bonding area

which leads to improved adsorption force of the surface. The bonding performance is optimal when the anodizing voltage was 25V.