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Adhesion it is known that the bond strength varies depending on the interaction of the material surfaces with each other and the surface morphology of the samples. Sufficient surface conditions are required to achieve good adhesion. It is important how the surface morphology, roughness values and free surface energy (SFE) values affect the bond strength and the relationships between these values. The aim of this study was to investigate the relationship between surface morphology, roughness values, contact angle and SFE values of hybrid etched surfaces with chemical etching, sandblasting and both sandblasting and chemical etching. Different surface morphologies were formed of the surfaces etched with different techniques. Contact angle values were determined by using different liquids on the surface of the samples with different surface morphologies. In addition, the surface morphology of the etched AA7075 samples was analyzed by scanning electron microscope (SEM) and 3D profilometer, and surface roughness values were determined.Different surface morphologies of the etched surfaces were formed by different techniques. The SFE values of the surfaces give us information about how wettable the surface is. For this reason, the surface roughness andn SFE values of AA7075 surfaces were compared and the mechanical and thermodynamic relations of the surfaces were revealed in the study. OWRK and Zisman methods were used in the calculations of SFE and it was seen that the values obtained from the two methods were consistent with each other. The highest SFE values were obtained on hybrid etched surfaces with sandblasting+0.5M NaOH and sandblasting+1M NaOH. Surface roughness values took different values in each surface treatment. As a result, it is seen that there is no direct relationship between surface roughness values and SFE. [ABSTRACT FROM AUTHOR]

Bimetallic or layered materials are an important group of advanced engineering materials, which are the materials where the physical, mechanical and thermal properties of the core particle can be improved. Therefore, in this study, the fabrication of silver-plated copper bimetallic particles was investigated by electroless coating method. Moreover, in this study, the effect of the amount of ion trapping / reducing agent in the electroless coating method on the physical properties of the bimetallic particles obtained as a result of the coating was investigated. Morphology, microstructure and silver layer thickness of the silver coated copper particles were characterized by scanning electron microscope (SEM) and Xray diffraction. SEM investigations revealed the presence of a silver coating layer on copper particles in the range of 0.873 - 2.3 μm. This result showed that the silver coating layer can be successfully synthesized on copper particles by using the electroless coating method. Thus, low cost of copper and high thermal conductivity and oxidation resistance of silver are combined in a single metal particle. [ABSTRACT FROM AUTHOR]

In the study, Spray pyrolysis technic was used to grow Ag-doped CdO thin films on Indium Tin Oxide (ITO) substrates. Temperatures of ITO substrates were fixed at 400⁰C. The structural and morphological properties of the thin films were investigated by X-Ray Diffraction (XRD) and Scanning Electron Microscope (SEM) devices. According to XRD results, the thin films have polycrystalline cubic structure and the average crystal sizes of thin films with Ag dopant are around 23 nm. According to Scanning Electron Microscope (SEM) images, changing of Ag dopant ratio does not effects surface morphology of samples significantly. [ABSTRACT FROM AUTHOR]

In this study, Ni-Co alloy coatings were prepared on the steel substrates with electrodeposition method from a sulphate baths using power supply. The effect of Co content in electrolyte on the composition, phase structure and surface morphology of alloy coating were investigated. The prepared coatings were characterized using X-ray diffraction (XRD) and scanning electron microscope (SEM). According to the results, Co concentration in the electrolyte affects the properties of the Ni-Co alloy coating layer. There is a serious increase of Co content deposited Ni-Co alloy coating when the Co concentration is increased in the electrolyte. The both FCC and HCP crystal structures of Ni-Co alloy coating layer began to transformin into HCP structure with increasing amount of Co content. At the same time, a change in the surface morphology was observed with an increase in Co ratio in the alloy coating layer and a more granular structure was formed. [ABSTRACT FROM AUTHOR]