O. S. I. Fayomi

Nanoparticle dispersion, microstructure and thermal effect of multi-doped ZrO2/SiC from sulphate induced electrolyte

Effort to improve the hardness and thermal resilient properties of coating for advanced engineering applications has necessitated this study. Zn sulphate electrolyte was induced with ZrO2-SiC composite particulate at varied current density of 1.5 and 2.0 A/cm2 for 10 minutes. The incorporated composite particles of ZrO2/SiC were varied in other to examine their mechanical responses on zinc electrolyte. The coated films were characterised with scanning electron microscope with attached electron dispersion spectroscopy (SEM/EDS) and atomic force microscopy (AFM). The micro-hardness properties of the coated and thermal aged alloy were determined with high diamond micro-hardness tester. The anti-corrosion progression was examined using linear polarization technique in 3.65% NaCl. From the results, the incorporation of the composite matrix was found to impact significantly on the surface and microhardness properties. The co-deposition of composite submicron on the zinc electrolyte revealed that homogenous grain structure was obtained. To this end, a boost in the performance characteristics was attained due to effective co-deposition parameters in the electrolyte.

Evaluation of Composition, Microstructure Characterization and Interfacial Properties of Zn—SnO2 Metal Matrix Composite Coating

In this paper the microstructure and tribological behavior of Zn—SnO2 (Zn—Sn) alloys produced through chloride and sulphates co-deposition is presented for comparison. 7.0 wt % SnO2 was added to Zn bath and deposited at 0.3 V. The interfacial effect and microchemistry of the fabricated composite was studied by optical microscope, X-ray diffraction (XRD), scanning electron microscope (SEM) equipped with energy disperse spectrum (EDS). The tribological behavior of the metal composites with SnO2 particles as reinforcement was studied using reciprocating sliding tester. The scanning electron microscopy (SEM) and atomic force microscope (AFM) of the composite surfaces indicates that there is good interfacial interaction between the alloy formulated matrixes made from the two baths and the substrate. Reasonable uniform distribution of Sn metal phase particulates is shown for both coating alloy. Increases in hardness and wear resistance are attributed to the uniform and coherent precipitation in the metal interface especially for Zn—7Sn—S—0.3V. In general, 7 wt % Sn additions to the bath showed more hastening to improved surface properties and better mechanical characteristics.

The effect of particulate strengthening on microstructure and mechanical characterization of binary-modified composites on mild steel:

This article presents the microstructure, tribological behavior, and hardness properties of the Zn-TiO2 functional composite coating produced using electrolytic co-deposition technique. The 7.0–13.0 weight fractions of Ti particles were incorporated in a Zn bath to form Zn-TiO2 alloy in the presence of other additives. The microstructural properties of the fabricated coating were investigated using a scanning electron microscope equipped with an energy-dispersive spectroscope, X-ray diffraction, and an atomic force microscope. The anticorrosion behavior in 3.65% NaCl medium was studied using potentiodynamic polarization technique and characterized using high-resolution optical microscope. The hardness and wear properties of the coated alloys were measured with high diamond microhardness tester and reciprocating sliding tester, respectively. From the results, the increases in hardness and wear resistance are attributed to the formation of the incorporated particulate and uniform precipitation of the metal grains at the metal lattice. The contribution of TiO2 particles especially with Zn-13Ti-0.3 V-S provides new orientation of metal–matrix-modified coated structure and decrease in friction coefficient. The anticorrosion resistance characteristics were found to improve significantly in response to concentration of additive.

Data analysis and study of the influence of deposition power on the microstructural evolution and functionality of metallic phase composite coating

In anticipation for resolution of deterioration catastrophe on metallic materials, researches in the field of corrosion remains. Zn–Ni–NbO2 deposits were obtained on mild steel substrate using D.C. power source. The thermal stability properties of the coatings were determined by micro-hardness evaluations before and after heat treatment at 250 and 350 °C. The surface structure analysis was done by Scanning Electron Microscope and X-ray diffraction while the wear evaluations were obtained and compared. The weight gain and coating thickness were obtained and found to be in correlation with the wear results. The coating developed in this study is recommended for metallic surface improvement engineering applications.