Morphological and Hardness Studies of Electroless Ni-P-ZrO₂ Nanocomposite Coatings on Mild Steel

Abstract:

Zirconia-reinforced nickel–phosphorus matrix (Ni–P–ZrO2) nanocomposite coatings were prepared by electroless (EL) coating technique and compared with plain Ni–P deposits. Nano-sized second phase ZrO2 particles (5–10nm) were synthesized by coprecipitation method. An alkaline hypophosphite EL bath is used with a suspension of zirconia nano-particles (4 g/L) during the process for the synthesis of Ni-P-ZrO2 composite coating at temperature 90±2°C and pH 9.0±2 respectively. The coating’s surface morphologies were examined under Scanning electron microscope (SEM), the average globular size of about 50μm was observed having the lateral growth followed by vertical growth. Phase analysis by XRD confirmed the presence of Ni and ZrO2.The grain size within the globules had been calculated by Scherrer formula= 0.9λ/βcosθ.The heat treatment (400 0C, 1 h) enhances the mechanical properties like hardness of the composite deposits.

• Periodical: Advanced Materials Research (Volume 585)
• Pages: 478-482
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.585.478
• Online since: November 2012
• Authors: Preeti Makkar, R.C. Agarwala, Vijaya Agarwala
• Keywords: Electroless (EL), Nanocomposite, Ni-P-ZrO₂, Reinforcement, Second Phase Particles

References

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