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The annealing process and shape are expected to significantly affect the magnetic properties and giant magnetoimpedance (GMI) effect of magnetic amorphous ribbon. Here, the GMI effect in the annealed samples of FeCoSiB with different aspect ratios was studied at the frequency range between 1 and 40 MHz. Magnetic properties and microstructures of samples were investigated by vibrating sample magnetometer and X-ray diffraction. With the increasing of annealing temperature, the coercivity was decreased from 1.1 Oe at room temperature to 0.18 Oe at 400 °C annealing temperature, and the sensitivity of GMI effect increased from 10%/Oe to 140%/Oe. The aspect ratio of the ribbon was found to affect the excitation frequency, which leads the GMI effect to the maximum due to the shape induced demagnetization field, regardless of the annealing temperature. [ABSTRACT FROM PUBLISHER]

In this paper, the influence of thermal annealing on the elastic-plastic behavior of Al-Si-Cu films under uniaxial and biaxial tensile stress states is described. For the mechanical evaluation of the films, we used an in-plane biaxial tensile test equipment that was specially designed and developed. In the uniaxial tensile test in which the strain rate was varied from 4.0\times 10^-4 to 5.0\times 10^-3~s^-1, annealing at 623 K (350^\circC) in N2 gas for 1 h did not affect the Young's modulus. The mean value was found to be 64.5\pm 5.6~GPa. The yield strength showed annealing dependency. The mean yield strength was 168.5\pm 2.2~GPa and 128.1~\pm~9.7~GPa for as-deposited and annealed films, respectively. In the biaxial tensile test in which the strain rate ratio was changed between 1:1 and 1:5 in Cartesian coordinates, tensile force and displacement were well controlled. The stresses at the time of yielding were fitted well using the yield equation of Hill with different Lankford coefficient values. X-ray diffraction and electron backscatter diffraction (EBSD) analyses demonstrated that the films had a <1\,1\,1> fiber texture. The grain growth and sharpening of the texture with annealing were observed in the EBSD analysis. Auger electron spectroscopy analysis suggested that a reduction in yield strength after annealing was related to Cu segregation at the grain boundaries, in addition to grain growth during annealing. [2012-0140] [ABSTRACT FROM PUBLISHER]

Al-rich \Al2\O3 thin films are synthesized by radio-frequency magnetron sputtering, followed by thermal annealing at 500 ^\circ\C for different durations to form Al/Al-rich \Al2\O3/p\-Si diodes. The annealing causes reactions at the Al-rich \Al2\O3/\Si interface, leading to an increase in Al concentration in the interface region. As a result, the current conduction of the diode is significantly enhanced, which results in anomalous capacitance–voltage ( C–V) characteristics. The anomalous behaviors can be eliminated by reconstructing the C–V curve based on a four-element circuit model. The resistance of the Al-rich \Al2\O3 layer extracted from the C– V reconstruction shows power-law voltage dependence correlated with the current-conduction measurement. [ABSTRACT FROM AUTHOR]

This paper presents a design-of-experiments study on the effect of annealing and simulated reflow on tin whisker growth. Copper, brass, and alloy 42 coupons plated with either bright or matte tin were subjected to one of three elevated temperature exposures. After the elevated temperature exposures, specimens along with a set of control specimens were then kept in room ambient conditions and monitored periodically using an environmentally scanning electron microscope. Surface observations up to 16 months of room ambient exposure revealed that tin whiskers formed on the surfaces of each specimen. However, various differences in whisker growth between the matte- and bright tin-plated specimens were observed. Columnar-type whiskers grown on the matte tin plated specimens were initiated from one grain at the surface, as opposed to the growth on bright tin which were independent from the surface morphology. Maximum length and length distribution data for matte and bright tin plating for the various exposures are presented. The result of this study shows annealing to be effective in reducing the maximum length of whiskers, particularly on bright finished coupons [ABSTRACT FROM PUBLISHER]

Temperature dependence of the Brillouin shift in a commercially available dispersion-shifted fiber has been experimentally investigated in the range of 20 to 820°C. When the as-fabricated fiber underwent a temperature cycle in the entire temperature rage, the Brillouin shift exhibited a noticeable hysteresis having the maximum frequency discrepancy of 48 MHz or larger between heating and cooling processes. After the fiber was annealed for 9 h at 850°C, however, the hysteresis almost disappeared and, among repeated temperature cycles in the ranges of 20-820°C and of 500-800°C, the maximum frequency discrepancy was reduced to ±12.5 MHz or less. It is thus demonstrated that a suitably annealed fiber is reliable for the Brillouin shift-based distributed sensing over the wide temperature range. [ABSTRACT FROM PUBLISHER]

We investigated the effects of annealing on crystalline structures in the current screen layer for current-perpendicular-to-plane giant-magnetoresistive (CPP-GMR) films. The current screen layer of an oxidized CoFe had a crystalline structure. The thickness of current screen layer that had not been annealed was uniform, even though the current screen layer was deeply wavy. On the other hand, the current screen layers that had been annealed became smoother when the annealing temperature was high. This suggests that the current screen layer was reconstructed by annealing to reduce the surface energy at the interfaces. We also measured the transport properties of these CPP-GMR films to clarify the annealing effects on their crystalline structures. The resistance area product (RA) became smaller with increasing the annealing temperature. The magnetoresistance (MR) ratio had a maximum value of 6.2% at an RA of 1.2 Ωµm² when the annealing temperature was 320 °C. Calculations indicate that the results obtained are due to not only an enlarged pinhole area, but also reduced pinhole resistance. [ABSTRACT FROM AUTHOR]