Bulk and Rayleigh (or surface wave) velocities of ultrasonic waves in chromium coatings on steel were measured and an experimental correlation was found between the surface velocity and the hardness. Since qualitative coating evaluation is commonly made using hardnesses as a guideline, the possibility is herewith presented of using the so und velocities of surface ultrasonic waves for this purp...

zinc coating is formed by the heterogeneous assembly of the γ, γ1, δ, ζ and η phases whose mechanicalproperties greatly differ from each other. thermal strains resulting from large differences betweenthermal expansion coefficients are partially relaxed by the formation of a crack network. in order tomodel this phenomenon, initial hardness, thermal expansion coefficient αi and toughness (kic) of...

Metal Matrix Composite (MMC) coatings of Tungsten Carbide (WC) and Nickel (Ni) powder were produced using laser cladding process. A crack free good metallurgically bonded WC-Ni coating about 5mm thick from varying both energy density percent mixture Ni WC. In this study, the microstructure characterised optical microscope (OM), scanning electron (SEM) with EDS, while mechanical properties studi...

INTRODUCTION The use of diverse materials for medical purposes is continuously expanding. The modification of materials which are routinely applied in medical practice as well as the development and introduction of new materials require studies on their biological activity. The first steps in this process are the preliminary short-term screening tests for cytotoxicity and biocompatibility perfo...

A tensile mechanical test suitable to measure the adhesion between brittle coatings and ductile substrates was applied to measure the adhesion of painted layers on polypropylene blends. The test involves the tensile deformation of the painted assembly, resulting in the periodic cracking of the brittle coating on the ductile substrate. The interfacial shear strength was determined by measuring t...

Nanostructured alumina thin films were coated on stainless steel by Sol-Gel dip coating method. In order to prevent crack formation, Al2O3 films were kept in a solvent bath immediately after coating to reduce the rate of drying. Effects of calcination temperature and withdrawal speed on structural properties were analyzed using XRD and SEM. Topography and thickness of coat...

This paper is concerned with the investigation of the capability of Detonation sprayed Ni-Cr And Al2O3 13TiO2 coatings to improve the tribological and mechanical properties of grey cast iron. The present study describes and compares the mechanical and tribological properties of NiCr and Al2O3 13TiO2 D-Sprayed coatings deposited on two different substrates (GI250 and GIHC) Experiments using a tr...

Ultra-small gold nanoparticles incorporated in mesoporous silica thin films with accessible pore channels perpendicular to the substrate are prepared by a modified sol-gel method. The simple and easy spin coating technique is applied here to make homogeneous thin films. The surface characterization using FESEM shows crack-free films with a perpendicular pore arrangement. The applicability of th...