Abstract:

Electroless nickel-based coatings are an excellent method to improve the surface properties of materials such as wear, hardness and corrosion. On the other hand, aluminum alloys are used in many applications" due to their properties such as cheapness and lightness. In addition to these good properties of aluminum alloys, their poor surface properties are limited in some usage areas in the industry. In this study, electroless nickel-boron (Ni-B) coatings were applied to the aluminum surface to improve the surface properties of the aluminum alloys (6xxxx). In this study, the effect of deposition time (30, 60, 90 min.) on the hardness and corrosion properties of Ni-B coatings was investigated. Scanning electron microscopy (SEM) was used to study the surface morphology, and X-ray diffractometry (XRD) was used to examine the phase structure. According to the SEM analysis results, it was observed as a result of the studies that the morphology of the Ni-B coating changed from nodular structure to cauliflower-like structure with increasing deposition time. Also, the thickness of the coatings is increased with an increase in the deposition time. According to the study's results, although the highest average hardness value is obtained as 1140 Hv by the highest deposition time of 90 min, the highest corrosion resistance is obtained as 1.969x10-3 mpy by the lowest deposition time of 30 min.

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