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Understanding the relationship between the structure and magnetic properties of soft magnetic thin films is important in the development of magnetic sensors and electronic devices. This work has systematically studied how the annealing temperature changes the morphology and hence the magnetic properties of 60 nm FeGaSiB thin films. The as-grown and 100°C annealed films were amorphous/nanocrystalline with soft magnetic properties. As the annealing temperature increased, so did the coercive field of the films, which was found to be due to the formation of polycrystalline grains, with random texture. The grain size increased with increasing annealing temperature, while the Curie Temperature and magnetostriction constant decreased. For the saturation induction, there was a large decrease between the 100°C annealed film and the 250°C annealed film, due to the film morphology changing from amorphous to polycrystalline. Thus there is strong correlation between the crystallinity and the soft magnetic behaviour of FeGaSiB films.

The crystal orientation of ceramic substrates is an important factor affecting the interface structure of metal/ceramic composite materials. However, there is little information about the interface composed of metal films and ceramic substrates with a high-index plane. In this work, we predicted the interface structure between a Nb film and a MgO(112) substrate by calculating the interface separation works of different interface models by using the first-principles calculation method. The results showed that the preferred growth direction is Nb [120], and that the value of the interface separation work is 0.35 eV/Å2. The lattice mismatch between the film and substrate is less than 3%, implying that a coherent interface type is highly realizable in Nb/MgO(112). Furthermore, we analyzed the interface structures of Nb/MgO(100), Nb/MgO(110), Nb/MgO(111), and Nb/MgO(112) and found that the unique atomic configuration of the MgO substrate is the main factor determining the preferred interface structure of Nb/MgO.

Hydroxyapatite (HA) is one of the most attractive biomaterials and widely used as a bone substitute due to its compositions are similar to the minerals in teeth and bones. Understanding of natural HA properties are useful in order to produces high quality of HA. In this paper, we report an easy and low cost method to extract the natural HA from femur cow bone and subsequently sintered at different temperature from 900 oC to 1300 oC. Structural, composition and surface morphology of natural Hydroxyapatite (HA) at different sintering temperatures (900 ̊ C, 1000 ̊ C, 1100 ̊ C, 1200°C and 1300 ̊ C) were discussed. The HA structural, composition and surface morphology were studied by using X-Ray Diffractometer (XRD), Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM), respectively. The results show the main HA phases were detected in the range of 31.72o - 31.82o (2Ө) for all sintered HA corresponding to 211 plane. The crystallite size of HA increases with sintering temperature from 900 ̊C to 1100 ̊C. Spectrums of FTIR revealed the existences of functional groups of carbonate (CO3 2-), phosphate (PO4 3-) and hydroxyl (OH-) peaks. SEM micrographs presented small and homogenous grains from 900°C to 1100°C. The grains look interconnected as sintering temperature increased at 1200°C and 1300°C. From this study, sintering process was found to be an easy and low cost method to produce natural HA from femur cow bones.