Papers by Keyword: XRD Measurements

Abstract: 3C-SiC lattice parameters, both in-plane and out-of-plane, have been studied as a function of the temperature (up to 773 K) by performing X-Ray Diffraction (XRD) measurements in coplanar and non-coplanar geometry during the thermal treatments. A tetragonal distortion of the 3C-SiC cell has been observed, with a=b≠c, resulting from a tensile stress status induced by the presence of Si substrate. A linear expansion coefficient of about 4.404 × 10^-6 K^-1 at 773 K has been obtained for a 15 μm thick 3C-SiC film grown on (100) Si substrate. The discrepancy with the value reported in literature of 5.05 × 10^-6 K^-1 at 800 K [Slack et al., Journal of Applied Physics 46, 89 (1975)] may be related to the different nature of samples used.

Abstract: In this paper we present self-designed mould suction casting apparatus allowing preparation of bulk samples in a form of rods (1.5 mm in diameter and about 3 cm in length). Making use of the apparatus the following compositions of Fe80Nb6B14, Fe76.2Nb5.7B13.8Gd4.8, Fe69.9Nb5.2B12.2Gd13, Fe76.2Nb5.7B13.8Y4.8, Fe69.9Nb5.2B12.2Y13, Fe61.5Nb4.6B10.8Y23.1 alloys were prepared. Phase and microstructure identification were curried out by making use of X-ray diffraction measurements. The obtained results show that the constructed apparatus fulfill all conditions required for such technique. Gadolinium as an alloying addition causes full amorphization in the case of the Fe76.2Nb5.7B13.8Gd4.8 alloy. In the other cases the structure was found to be nanocrystalline which is discussed in the paper.