Essay Example on Investigate the structure Ultrasonic Velocities, Mechanical Properties, and Debye temperature.

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A series of superconducting composite YBa2Cu3O7 δ x Ni metal x 1 2 5 5 7 5 10 and 15 wt were prepared by the solid-state reaction method. Density and molar volume was determined using the immersion method X rays diffraction. XRD and scanning electron microscope SEM characterization were terminated for structural and microstructural analysis. The results showed the presence of orthorhombic peaks of YBCO in the whole composite samples with different lattice constants and how Ni addition affects the distortions in the orthorhombic unit cell of YBCO. A new technique has been used to measure the ultrasonic wave velocities longitudinal and transverse at 4 MHz ultrasonic frequency at room temperature. The mechanical parameters of the samples including longitudinal modulus shear modulus. Young’s modulus, Poisson’s ratio, and microhardness have been investigated from the viewpoint of the porosity and the connectivity between the formed phases.

Besides the Debye temperature was also determined as a function of Ni additions. The elastic moduli microhardness and Debye temperature have been improved up to 2 5 Ni then a decrease in all data observed with a further addition of Ni Quantitative analysis has been implemented to obtain more details about the structure of the composite samples based on orthorhombic phases the oriented grain size the porosity and the agglomeration between grains. The superconductor YBa2Cu3O7 δ YBCO has superior properties over other types of superconducting ceramics. 1 It has gathered a lot of attention because of its potential in many applications such as superconducting magnets, magnetic shields, magnetic bearings levitated systems and superconducting motors. 2 3 However practical applications of these materials are often limited because of their poor mechanical performance. 4 5 The mechanical properties such as strength.

Young’s modulus hardness, as well as the critical current density and critical magnetic field, are crucial for industrial applications of high-temperature superconductors.

 6 Ultrasonic methods are the convenient and most powerful methods to investigate the mechanical properties of solids. 7 14 In the case of the high Tc superconductors many ultrasonic measurements have been made and studied by several authors. 15 19 Researchers have studied the mechanical properties of YBCO and YBCO added Zn at low and room temperatures. 6 They detected that the elastic recovery ratio of the one wt ZnO added the YBCO sample which was higher than that of YBCO at both low and room temperature. Other papers such as that by Takanohashi 20 pointed to study the ultrasonic propagation in the sintered YBa2Cu3O7 x superconductors in order to investigate the elastic anomalies caused by the various lattice instability mechanism.


The ultrasonic velocities the mechanical properties and Debye temperature have investigated from the viewpoint of the porosity and elastic anomalies. Other papers such as those by Dominec 21 and Wu Ting 22 summarized the elastic constants of Bi Sr Ca Cu O La Sr Cu O and Y Ba Cu O YBCO superconductors and discussed the elastic anomalies lattice instabilities and their mechanisms. In addition, the elastic constant phase transitions and specific heat measurements in the Y1Ba2Cu4O8 and Y1 xCaxBa2Cu4O8 were employed and discussed. 23 While Graser et al 24 gave a detailed analysis by simulating the atomic structure of the grain boundaries in YBCO and identified the build-up of charge inhomogeneities as the dominant mechanism for the suppression of the supercurrent. The elastic moduli the flexural strength splitting tensile strength and the hardness of YBCO and Gd 123 added with 15wt Ag at 77 K and 300 K were investigated by Konstantopoulou et al 25 All samples showed a very good mechanical behavior at both 77 and 300 K while those behavior are more homogenous with Gd 123 added Ag While Jan Pinc et al 2 recently gave a presenting mechanical and superconducting properties such as the hardness and comprehensive strength of YBaCuO and GdBaCuO at room temperature. The phase composition of the two commercial fabricated samples was characterized by XRD and EDS measurements and its structure was examined by SEM and optical microscopy. W Malaeb 26 studied the effect of CoFe2O4 x and ZnFe2O4 x nanosized ferrites on the elasticity parameters of Gd 123 phase measured by the ultrasonic Pulse echo method at room temperature and compared the data with that of measured by Vickers microhardness In our current study we have made the experiment of ultrasonic propagation in the sintered YBa2Cu3O7 δ added ferromagnetic metal. Ni to investigate the structure ultrasonic velocities, mechanical properties, and Debye temperature.

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