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In this research the size controlled synthesis of FeCo nanoparticles was done using a quaternary microemulsion system. X-ray diffraction and high resolution transmission electron microscopy of as-synthesized nanoparticles confirm the formation of FeCo alloy nanoparticles. The effects of two process parameters, namely, water to surfactant molar ratio and molar concentration of metal salts, on the size and size distribution of nanoparticles were discussed by the aid of transmission electron microscopy. The size dependency of magnetic properties was also investigated using a room temperature vibrating sample magnetometer. The superparamagnetic-ferromagnetic and single domain-multidomain transition sizes were determined. Then the specific absorption rates at transition sizes were calculated and the best sample for magnetic hyperthermia treatment was introduced.

In this study, a simple, safe and cost-effective method was developed for fabricating the tungsten disulfide/carbon nanotube (WS 2 /CNT) hybrid nanoparticles via chemical vapor deposition (CVD) process. Hybrid nanoparticles used for reinforcing the aluminum matrix. The hybrid nanocomposites were prepared by powder metallurgy processing and consolidated by the Hot-Pressing process. The chemical composition and morphology of the WS 2 /CNT hybrid particles were studied by x-ray diffraction (XRD), filed emission scanning electron microscopy (FESEM), Raman spectra, Fouriertransform infrared spectroscopy (FTIR) and thermo gravimetric analysis (TGA). The results proved that the uniform, pure and tubular WS 2 / CNT hybrid nanoparticles were produced and WS 2 nanoparticles were decorated the CNT surface successfully. Optical microscopy (OM) and FESEM used for characterization of the microstructure of hybrid nanocomposite, indicate a good distribution of hybrid nanoparticles in the aluminum matrix. Maximum values of relative density, hardness and compressive strength were measured for sample with WS 2 /CNT ratio of 1:1. A relative density of more than 99.5% was obtained for this sample. Hardness and compressive strength were improved by 43% and 60% compared with pure aluminum respectively.

In this research, FeCo alloy magnetic nanofluids were prepared by reducing iron(III) chloride hexahydrate and cobalt(II) sulfate heptahydrate with sodium borohydride in a water/CTAB/hexanol reverse micelle system for application in magnetic hyperthermia treatment. X-ray diffraction, electron microscopy, selected area electron diffraction, and energy-dispersive analysis indicate the formation of bcc-structured iron-cobalt alloy. Magnetic property assessment of nanoparticles reveals that some samples are single-domain superparamagnetic, while others are single- or multi-domain ferromagnetic. The stability of the magnetic fluids was achieved by using a CTAB/1-butanol surfactant bilayer. Results of Gouy magnetic susceptibility balance experiments indicate good stability of FeCo nanoparticles even after dilution. The inductive properties of corresponding magnetic fluids including temperature rise and specific absorption rate were determined. Results show that with increasing of the nanoparticle size in the single-domain size regime, the generated heat increases, indicating the significant effect of the hysteresis loss. Finally, the central parameter controlling the specific absorption rate of nanoparticles was introduced, the experimental results were compared with those of the Stoner-Wohlfarth model and linear response theory, and the best sample for magnetic hyperthermia treatment was specified.