Synthesis of the Ni-Al coatings on different metallic substrates by mechanical alloying and subsequent laser treatment

Abstract

Abstract Ti-Al intermetallic coatings thickness of about 60–150 μm was fabricated on Al, Ti, and hypo-eutectoid steel substrates by mechanical alloying (MA) using a vibratory ball mill. The coatings was then laser treated to obtain homogenous and equilibrium structure. Phase composition and the cross-sectional microstructure of the coatings were investigated using X-ray diffraction and the Scanning electron microscopy respectively while chemical analysis of the coatings was carried out using Bruker energy-dispersive X-ray Spectrometer (EDS). Micro-hardness (HV) of the obtained coatings was observed to be increased more than twice after the deposition and subsequent laser treatment in comparison with microhardness of the initial substrates materials.. Surface roughness of the obtained coatings was also reduced significantly after laser treatment i.e. for Al substrate it reduced from 52 μm to 26 μm. The parameters of mechanical alloying and laser treatment used in this work provided a successful way to deposit nano-structured intermetallic coatings with homogenous and smooth surface finish and high value of micro-hardness.