The effect of annealing on magnetic properties of a cold-rolled Fe₇₉B₁₆Si₅ amorphous ribbon has been examined to find a way to improve the deformation-induced degradation of soft magnetic properties. Annealing between the Curie temperature and the crystallization temperature is very effective to improve the deteriorated magnetic properties of the 10% cold-rolled ribbon. After annealing between these temperatures for a few minutes, the shape of the hysteresis curve reverts to that prior to cold-rolling. During subsequent anneals, the change in the curve of the cold-rolled ribbon is nearly identical with that of the as-quenched ribbon. The activation energy spectrum characterizing the recovery process has been calculated by using the activation energy spectrum (AES) model. The resultant spectrum revealed two peaks. This indicates that two distinct relaxation mechanisms are involved in the process.

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The chemical diffusion in titanium-molybdenum system has been studied in the temperature range of 1200 to 1500 K using pure metal diffusion couples. The concentration penetration profiles have been established by employing an electron probe microanalyser. The chemical diffusion coefficients have been evaluated following the Boltzmann-Matano method. The concentration and temperature dependence of chemical diffusion coefficients have been established. The expression for the chemical diffusion coefficient for a given composition (C_Ti) and temperature (T) can be written as
\ ildeD_(CTi)=2.75×10⁻⁵exp(−4.14C_Ti)exp[−(212.647+68.16C_Ti)kJ·mol⁻¹⁄RT], m²·s⁻¹.
The data have been rationalised on the basis of the Vignes-Birchenall relationship.

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The phenomenological calculation of the L1₀-disorder phase equilibria in the Co–Pt binary system is attempted by using the Lennard-Jones type potential combined with the tetrahedron approximation of the Cluster Variation Method. Thermal vibration effects based on the Debye-Grüneisen model are introduced into the calculation scheme. The calculated thermodynamic properties and phase diagram are presented and the thermal vibration effects on phase stability are examined.

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The different transformation behavior towards amorphization observed during mechanical alloying of (Al_0.88Ni_0.08Co_0.04)_100−xZr_x powder mixtures where x=0 to 4 at.% was characterized by means of X-ray diffraction patterns, scanning electron microscopy, differential scanning calorimetry and transmission electron microscopy. It was found that mechanical alloying of Al, Ni and Co elemental powders without Zr leads to the formation of nanocrystalline equilibrium phases fcc-Al solid solution and (Co, Ni)₂Al₉ compound. Upon disordering the resulting phases it was concluded that amorphization cannot be obtained. The measured enthalpy stored ΔH_s during deformation was found less than 1 kJ/mol. Whereas, the crystalline to amorphous phase formation was observed when a few at.% of Zr was added into the Al–Ni–Co ternary system. The reasons seem to result from the fact that at the Al/Ni, Al/Co and Ni/Co the criteria for amorphization by solid state amorphization during mechanical alloying are not fulfilled, while at the Al/Zr, Ni/Zr and Co/Zr interfaces these criteria are satisfied and the amorphization is observed at an early stage of deformation. Increasing Zr substitution increases the thermal stability of the amorphous phase, which explains the complete amorphization for compositions containing Zr up to 4 at.%. The crystallization evolves in two stages: precipitation of Al phase dispersed in an amorphous matrix which crystallized in turn. The total exothermic heat ΔH_c released vary from 2.2 to 3.1 kJ/mol in going from 1 to 5 at.% Zr. The activation energy (E_a) and crystallization temperature (T_x) both increased with increasing Zr addition.

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In this work an analytical numerical procedure is presented based on the linear viscoelasticity and the information provided by the torsion pendulum at the variable moment of inertia, for determining all the activation parameters in the stress-induced ordering phenomenon. This procedure also determines if a distribution of relaxation times is present and if its choice is appropriate.
Measurements of the Snoek relaxation in the niobium-oxygen and tantalum-oxygen systems with different interstitials contents were carried out and the new procedure was applied for determining all the activation parameters in the Snoek relaxation.
On the other hand, the mode of writing the internal friction with a distribution function associated with it, was verified experimentally.
Furthermore, an anomalous behaviour of the relaxation strength with the temperature, for the Snoek relaxation, has been found.

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The (100), (110) and (111) surface of MgO were observed at an atomic scale using an atomic force microscope. It was identified that the line defects existed on each surface and that the surface structure of MgO was different from the bulk one. It can be infered that all the bright spots in the AFM images correspond to the positions of the oxygen atoms in the case of MgO.
A factor affecting the wettability of MgO single crystal by liquid metals was discussed on the basis of the AFM observations. It gets cleared that the interaction between the oxygen on the surface and the magnesium or oxygen on the second layer affects the crystallographic orientation dependence of the wettability of MgO single crystal by liquid metals.

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Effects of B content on the sintering behavior of Nd₁₅Fe_85−xB_x (x=4–10 at%) alloy powders were investigated through microstructural observations, and measurements of DTA, linear shrinkage and magnetic properties. In the case of x≥6 at%, a liquid phase forms from ternary eutectic reaction of Nd-rich, Nd₂Fe₁₄B and Nd_1.1Fe₄B₄ phases at 938 K. While the shrinkage below 1300 K is very small because of a lack in the amount of liquid phase, remarkable shrinkage occurs when the sintering temperature is raised above 1300 K. On the other hand, in the case of x<6 at%, a liquid phase forms from a reaction between Nd-rich and Nd₂Fe₁₇ phases at 963 K. In this case, shrinkage starts rapidly corresponding to the appearance of liquid phase and continues at a constant rate to higher temperatures. This is probably due to increase of the amount of liquid phase and the reaction between Nd₂Fe₁₇ and Nd₂Fe₁₄B phases, causing the liquid flow and solution-precipitation.

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An anomalous small angle X-ray scattering (anomalous SAXS) method has been applied to obtain a possible origin of structural inhomogeneity in amorphous Zr₃₃Y₂₇Al₁₅Ni₂₅ alloy annealed at 773 K for 300 s. The remarkable decrease in intensity is detected for Ni and Zr whereas an increase is clearly observed for Y, when the incident energy approaches to the respective K-absorption edge. Several models have been tested for describing these new experimental data and the Y-rich phase is suggested to be one of the possible origins for structural inhomogeneity by explaining the anomalous SAXS intensity variations at three absorption edges of Ni, Y and Zr.

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Al-based amorphous alloy wires with composition Al₈₅Ni₁₀Ce₅ were produced by a melt extraction method using a copper wheel with a steep edge. The wire has a circular cross section and no appreciable trace resulting from the use of copper wheel is seen on the outer surface. The wire diameter is in the range of 40 to 70 μm and tends to decrease with increasing rotation speed of the wheel. The onset temperature of crystallization, the glass transition temperature and the heat of crystallization are 531 K, 546 K and 0.37 kJ/mol, respectively, for the wire with a diameter of about 70 μm, in agreement with those for the melt-spun amorphous ribbon with a thickness of about 15 μm. The wires have good bending ductility and a high tensile strength of 950 MPa. The maximum wire diameter of 70 μm is nearly the same as the maximum ribbon thickness for the formation of ductile amorphous alloy with the same composition by the conventional melt spinning method. The high cooling rate for the present process is accomplished presumably because the supercooled liquid with a small volume and a large outer surface area to volume ratio is solidified homogeneously without contact of other substances.

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