Preparation and Properties of Graphene/Nickel Composite Coating Based on Textured Surface of Aluminum Alloy.

This study carried out a novel duplex surface treatment on aluminum alloy base to explore the potential improvement of wear and corrosion resistance. Regular arrayed dimple surface texture (DST) and groove surface texture (GST) were fabricated by using laser processing on 6065 aluminum alloy matrix (6065Al). Electrochemical deposition of Ni and Graphene/Ni coatings on textured surface was then performed in electrolytes with concentrations of 0, 0.5, 1 and 1.5 mg graphene. Surface morphology such as diameter of dimple and width of groove measured by C-PSCN stereo microscope presents addition of graphene helps to refine and homogenize the coating. Corrosion resistant properties of the duplex surface treatment were examined by electrochemical corrosion tests and wear resistant properties were tested by UMT-Tribo Lab friction and wear tester in a dry sliding condition at room temperature. Electrochemical corrosion tests results show that the corrosion resistance of samples is related to the specific surface texture and the dimple texture can improve the electrical corrosion parameters, such as the electrode potential, greatly. Friction and wear tests show that the textured Gr/Ni electroplating coating with the 1.5 mg graphene content has best wear properties under vertical friction and each index, such as the coefficient of friction and wear trace width, are superior to other conditions of samples.