Remarkable improvement in properties of NI-B coatings by the addition of mixed oxide nanoparticles

Abstract

A comparison of properties of Ni-B and Ni-B-ZrO2-Al2O3 nanocomposite coatings synthesized through electrodeposition process is presented to elucidate the beneficial role of addition of mixed nanoparticles of ZrO2 and Al2O3 into Ni-B matrix. It is noticed that the addition of nanoparticles of ZrO2 and Al2O3 into Ni-B matrix has significant influence on its structural, thermal, surface, mechanical and electrochemical properties. Incorporation of mixed nanoparticles of ZrO2 and Al2O3 into Ni-B matrix results in significant grain refinement, enhancement in crystallinity, remarkable improvement in mechanical properties and corrosion resistance. The improvement in hardness can be attributed to grain refinement of Ni-B matrix and dispersion hardening effect of insoluble hard ceramic nanoparticles. The improvement in corrosion resistance can be presumably regarded as the effect of reduction in active area of Ni-B matrix by the presence of inactive nanoparticles of ZrC2 and Al2O3. Copyright