Influence of ball milling duration of quarry dust on the properties of nickel-quarry dust composite coating

The research focuses on the effect of various ball milling duration on the surface morphology, hardness and wear properties of nickel-quarry dust (Ni-QD) composite coating electrodeposited on aluminium alloy 6061 (AA6061) substrate. The quarry dust particles were prepared by ball milling process at 5, 10, 15 and 20 hours. X-ray Fluorescence (XRF), X-ray Diffraction (XRD) and Scanning Electron Microscope (SEM) analyses were carried out in order to investigate the influence of ball milling duration on the prepared quarry dust as well as the produced composite coating. In addition, microhardness Vickers and wear testing of Ni-QD composite coatings were also performed in this study. The results obtained indicate that the quarry dust particle size is influenced by increasing the ball milling duration. Increase in ball milling duration from 5 to 20 hours results to finer particle size, which improves the microhardness of the Ni-QD composite coatings from 190.6 HV to 282.2 HV. The increase in microhardness values is due to the increase incorporation of fine quarry dust particle in the Ni coating. Furthermore, the wear resistance of the Ni-QD composite coatings were improved, as the ball milling duration increased from 5 to 20 hours.