ABSTRACT
Titanium-based alloys are used in orthopedic applications as fixation elements, hard tissue replacements in artificial bones, and dental implants. Despite their wide range of applications, metallic implant defects and failures arise due to inadequate mechanical bonding, postoperative clotting problems, aseptic loosening, and infections. To improve the surface bioactivity and reduce the corrosion rate of the Ti6Al4V alloy, multi-layered coatings (HAp, BG, Cs, and Hep) were applied via electrophoretic deposition (EPD). XRD images showed the presence of HAp within the coating. In vitro investigation: cell line NIH-3T3 fibroblasts were seeded on the non-coated and coated Ti6Al4V substrates, and their cellular behavior was evaluated. The results indicated that the HApBGCsHep coating could enhance the adhesion and proliferation of NIH 3T3 cells. In addition, the potentiodynamic polarization results are compatible with the in vitro outcome.
ABSTRACT
In this work, the microstructure, mechanical properties, and corrosion behavior of the Mg-1Zn-0.6Ca matrix alloy (ZX10), reinforced by adding various amounts of nanodiamond particles (0.5, 1, and 2 wt.%), prepared by the ultrasound-assisted stir-casting method, were investigated as they are deemed as potential implant materials in biomedical applications. Microstructure, nanoindentation, mechanical tensile, immersion, and potentiodynamic polarization tests were performed for evaluating the influence of the addition of nanodiamond particles on the alloy's mechanical and biocorrosion properties. The results revealed that the addition of nanodiamond particles causes a reduction in the alloy's grain size. The alloy's nanohardness and elastic modulus values increased when the amount of added nanodiamond particles were increased. The nanocomposite with an addition of 0.5% ND showed the best composition with regard to an acceptable corrosion rate as the corrosion rates are too high with higher additions of 1 or 2% NDs. At the same time, the yield strength, tensile strength, and elongation improved slightly compared to the matrix alloy.
ABSTRACT
The aim of this study was to investigate the effect of adding 1, 2 and 4% wt of cerium on the microstructure, mechanical and corrosion properties of high pressure die casting (HPDC) Mg-4Sn alloys. Microstructure analyses of the alloys were carried out using X-Ray Diffraction (XRD) and Scanning Electron microscopy (SEM). The corrosion behaviors were determined with the potentiodynamic polarization and immersion tests in Hanks Balanced Salt Solution (HBSS), which is used as the artificial body fluid. The microstructural results showed that the addition of Ce to the main alloy creates new intermetallic phases (Ce5Sn4 and MgSnCe). In addition, Ce addition provided effectively the grain refinement of the alloys. While the hardness and yield strength of the Mg-4Sn alloy enhanced continuously with increasing Ce content, the tensile strength and elongation reached up to 2% wt. The corrosion resistance of the main alloy was improved by the addition of 1% wt of Ce. However, the Ce content, which is more than 1% wt decreased corrosion resistance.
