The cathodic deposition (CD) technique utilises specific metal ions in an electrolyte to acquire electrons in the presence of an applied electric field, which are reduced and deposited on the cathode surface. This technique typically uses lower voltages and is usually applied to non-valve metal surfaces. Direct application to valve metal surfaces produces poorly adhered coatings. Micro-arc oxidation (MAO) technology uses arc discharge and high voltage penetration to form a ceramic coating on the valve metal surface, which plays an important role in improving the wear and corrosion resistance of titanium alloys. In this paper, MAO technology is used as a pretreatment, which not only solves the problem that CD technology cannot be applied to titanium alloy, but also prepares a coating with excellent friction and corrosion resistance.

Hongkang Pan a, Hailin Lu a,*, Guangming Xub, Zhanshuai Fana, Fan Yanga, Ping Liub,c,. *.  Preparation of MAO-Ni/ZrO2 composite coating on titanium alloys by micro-arc oxidation and relatively high voltage cathodic deposition techniques.[ J]. Journal of Alloys and Compounds. (Impact Factor: 5.8, CAS Region II, TOP) 

Fig. 1 SEM image of sample surface

Fig. 2 Macroscopic morphology of the sample surface