Search Results (3)

Sports are becoming an important part of everyday life. In this study, an excellent Ni-SiC nanocomposite was prepared on the dumbbell surface using the pulse electrodeposition (PE) method to improve the durability of sports equipment and prevent sports injuries. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), abrasion testing, triboindentry, and X-ray diffraction (XRD) were used to evaluate the impact of plating conditions upon the microhardness, microstructure, morphology, and wear behavior of the fabricated coatings. The obtained results showed that several SiC and TiN nanoparticles were incorporated into Ni/TiN-SiC nanocomposites obtained at 4 A/dm². SiC and TiN nanoparticles had mean diameters of 37.5 and 45.6 nm, respectively. The Ni/TiN-SiC nanocomposite produced at 4 A/dm² showed an excellent mean microhardness value of 848.5 HV, compared to the nanocomposites produced at 2 and 6 A/dm². The rate of wear for Ni/TiN-SiC nanocomposite produced at 4 A/dm² was 13.8 mg/min, demonstrating outstanding wearing resistance. Hence, it has been suggested that the Ni/TiN-SiC nanocomposite can effectively reduce sports injuries. Full article

The surface modification of NiTi shape memory alloys is a method for increasing their multi-functionalities. In our solution, hydroxyapatite powder was mixed with a chemically synthesized silicon dioxide/silver (nSiO₂/Ag) nanocomposite in a different weight ratio between components (1:1, 5:1, and 10:1) and then electrophoretically deposited on the surface of the NiTi alloy, under various time and voltage conditions. Subsequently, uniform layers were subjected to heat treatment at 700 °C for 2 h in an argon atmosphere to improve the strength of their adhesion to the NiTi substrate. A change in linear dimensions of the co-deposited materials during the sintering process was also analyzed. After the heat treatment, XRD, Raman, and Scanning Electron Microscopy (SEM) + Energy Dispersive Spectrometer (EDS) studies revealed the formation of completely new composite coatings, which consisted of rutile and TiO₂-SiO₂ glass with silver oxide and HAp particles that were embedded into such coatings. It was found that spalling characterized the 1:1 ratio coating, while the others were crack-free, well-adhered, and capable of deformation to 3.5%. Coatings with a higher concentration of nanocomposite were rougher. Electrochemical impedance spectroscopy (EIS) tests in Ringer’s solution revealed the capacitive behavior of the material with high corrosion resistance. The kinetics and susceptibility to pitting corrosion was the highest for the NiTi electrode that was coated with a 5:1 ratio HAp/nSiO₂/Ag hybrid coating. Full article

This work aims to improve the properties of aluminum foams including the mechanical properties and corrosion resistance by electrodepositing a SiC/TiN nanoparticles reinforced Ni–Mo coating on the substrate. The coatings were electrodeposited at different voltages, and the morphologies of the coating were detected by SEM (scanning electron microscope) to determine the most suitable voltage. We used XRD (x-ray diffraction) and TEM (transmission electron microscope) to analyze the structure of the coatings. The aluminum foams and the substrates on which the coatings were electrodeposited at a voltage of 6.0 V for different electrodeposition times were compressed on an MTS (an Electro-mechanical Universal Testing Machine) to detect the mechanical properties. The corrosion resistance before and after the electrodeposition experiment was also examined. The results showed that the coating effectively improved the mechanical properties. When the electrodeposition time was changed from 10 min to 40 min, the W_v of the aluminum foams increased from 0.852 J to 2.520 J and the σ_s increased from 1.06 MPa to 2.99 MPa. The corrosion resistance of the aluminum foams was significantly improved after being coated with the Ni–Mo–SiC–TiN nanocomposite coating. The self-corrosion potential, pitting potential, and potential for primary passivation were positively shifted by 294 mV, 99 mV, and 301 mV, respectively. The effect of nanoparticles on the corrosion resistance of the coatings is significant. Full article