Effect of Annealing Temperature and Alumina Particles on Mechanical and Tribological Properties of Ni-P-Al2O3 Composite Coatings

摘要

In this study, the effect of annealing temperature and alumina particles on micro-hardness, corrosion, wear, and friction of Ni-P-Al2O3 composites coating is studied. The electroless nickel composite coating with various alumina particle content is deposited on a mild steel substrate. The corrosion behaviour and tribological behaviour (wear and friction) of the composite coated samples are investigated and compared with Ni-P coated samples. The micro-hardness, wear resistance, and corrosion resistance of the composite coating improved significantly after heat treatment (400 A degrees C) and in the presence of alumina particles. The composite coating deposited with alumina particle concentration of 10 g/L in an electroless bath and heat treated at 400 A degrees C shows excellent results compared to Ni-P, as-deposited Ni-P-Al2O3 coating and coatings heat treated at different annealing temperature (200 A degrees C, 300 A degrees C, and 500 A degrees C). Microstructure changes and composition of the composite coatings due to incorporation of alumina particles and heat treatment are studied with the help of SEM (scanning electron microscopy), EDX (energy dispersive X-ray analysis and XRD (X-ray diffraction analysis).