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The parameter such as reinforced particles plays a role in controlling the microstructure and eventually influences the mechanical properties of the composite coating. The microstructure strength of composite coating come from phase combination of the matrix and its reinforcement. This study described the effect of the electrodeposition process parameters of Si3N4 particle concentration on the Ni-TiN-AlN/Si3N4 composite coatings. Therefore, the experiment was performed by varying Si3N4 particles concentration in range of 0.2, 0.4 and 0.6 g/L in electrodeposition process. The coating morphology and crystal structure were characterized by mean of Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD), respectively while the coating microhardness was tested by using Vickers hardness test. The calculations were performed to analyze the coating stress from XRD data and presented its relation with the coating microhardness. The analysis results displayed that the uniform surface morphology of composite with the evolution of nitride particle aggregation was observed at various S3N4 particles concentration. In general, the uniformity morphology was due to the refinement of Ni crystallite size. The crystal structure was noticed prominently by Ni, TiN and AlN grains while Si3N4 grain was not observed due to its amorphous nature. In general, the increase of composite microhardness, as increasing Si3N4 concentration was attributed by the reducing Ni crystallite size lead to the increase of coating residual stress. [ABSTRACT FROM AUTHOR]

In this study, we have simulated and investigated electromagnetic properties of six types materials using a single layer metal backed absorber model that were determined at microwave frequencies 8.2 up to12.4 GHz. The reflection loss was simulated for different thicknesses in the range of 0.85 to 1.05 mm based on the relative complex permeability and permittivity referring to transmission line theory. The optimal microwave absorbing properties was be resulted by A3 sample. The minimum RL of −23.84 dB can be obtained at 10.72 GHz with thin thickness of 0.95 mm. This method paves a new avenue to design magnetic and dielectric absorbing materials.

We have investigated structure, magnetic and dielectric of La0.5Sr0.5Fe0.9Mn0.05Ti0.05O3 (LSFMTO) system using ultrasonic mixing method. LSFMTO system is driven by 40 kHz frequency and calcinate process up to 750°C for 30 minutes. Then sintering process also carried out by systematic various of temperature 900 °C, 1000 °C, and 1100 °C respectively, as same time previously. Very interestingly, the LSFMTO system exhibits ferroelectric (La,Sr)(Fe,Mn,Ti)O3 and ferromagnetic SrFe12019 properties and minor phase La2O3 by XRD interpretation analyzation. We have also carried out the measurement of LSFMTO system using a systematic applied the external magnetic field from 0 to 1 T and the electric polarization from 0 to 50 kV/m . The hysteresis curve of LSFMTO system shows the electricty coercive (Ec) increases while the saturation polarization (Pc) and the remanent polarization are tendency constant at the magnetic strength of 0.12 T. We believed that our finding of LSFMTO system is potensial to multiferroic material as magnetic sensor application.

We investigate ablation of Aluminum nanoparticle due to ultrashort high-intensity laser pulse. Molecular dynamics simulation is used to follow the evolution of the system and observe thermodynamics together with cluster properties. The energy given from the laser to the system is 1.5 eV/atom which is above ablation threshold and modelled using instantaneous and homogenous energization at the beginning of simulation. The evolution of the system shows a highly non-equilibrium state after the irradiation. Expansion of the sphere indicated that the system cannot survive from the temporary high tensile pressure that leads to ablation. While the high temperature consecutively responsible for the formation of cluster, it also indicated that the system is relaxed at the end of the simulation.

We study the structural change of Aluminum thin film due to heat treatment. The film is heated up from room temperature of 300 K to 1000 K where it is already above melting temperature of Aluminum. Molecular dynamics simulation is employed to observe the behavior of the system since it provides atomistic detail. The structural transformation is investigated based on the structure factor and pair distribution function which indicated the broadening of the peak of crystal structure due to phase transition of the material. Atomistic information revealed the local lattice structure change based on Common Neighbor Analysis (CNA) methods.