An extremely high tensile strength (σ_f) of 1340 MPa combined with good bending ductility was obtained as a mixed structure consisting of nanoscale icosahedral (I) particles with a size of about 40 nm surrounded by a thin fcc-Al layer with a thickness of about 2 nm in rapidly solidified Al_99−x−yCr_xCe₁Co_y alloys containing 0 to 5%Cr and 0 to 1.5%Co. Furthermore, each I-particle has a random orientation and contains a high density of phason defects and subnanoscale approximant crystalline regions. The replacement of Co by Mn, Fe, Ni or Cu causes the decrease in σ_f through the increases in the particle size of the I-phase and the width of the Al phase as well as the decrease in the density of phason defects in the I-phase. The unique mixed structure is formed through the process of the precipitation of the primary I-phase, followed by the solidification of the remaining liquid as an Al phase. The good ductility for the alloys containing the I-phase as a main constitute is presumably due to the ease of the sliding along the interface between I- and approximant crystalline phases as well as the existence of the Al phase which surrounds the I-phase. The high σ_f value is interpreted by the effective contribution of the I-particles as a strengthening phase because of the achievement of a good ductile nature for the mixed phase alloys.

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The precipitation of a primary Al phase upon annealing of amorphous Al₈₇Ni₁₀Ce₃, Al₈₇Ni₇Cu₃Ce₃ and Al₈₇Ni₈Ag₂Ce₃ alloys was found to occur only through a growth mechanism, based on the result that the exothermic reaction due to the precipitation of Al phase on the DSC curve does not have an incubation stage. The activation energy for the growth of the Al phase decreases from 1.82 eV for the Al–Ni–Ce alloy to 1.44 to 1.56 eV for the Al–Ni–M–Ce (M=Cu or Ag) alloys and the annealing temperature and time regions where the Al phase grows extend by the replacement of M for Ni. The particle size of the Al phase decreases from 9 nm for the ternary alloy to 3 to 5 nm for the quaternary alloys, accompanying the significant increase in the number of the Al particles. The extremely fine mixed structure consisting of nanoscale Al particles embedded in the amorphous matrix is formed in the Al–Ni–M–Ce alloys containing Cu or Ag elements which are soluble to the Al phase. The formation of the mixed structure is presumably due to the combination of (1) the necessity of the redistribution of the M elements for the growth of the Al particles resulting from the difference between the soluble content of the M elements into the Al particles and the nominal M content in the amorphous matrix, and (2) the increase in the number of the pre-existing nuclei of Al-rich zone resulting from the increase in the apparent Al content caused by the replacement of Ni by the M elements. The finding of the M elements leading to the refinement of the nanoscale Al particles is important in the subsequent development of the nanoscale mixed phase alloys.

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The R-phase transformation of a 50Ti48Ni2Al alloy has been investigated by means of calorimetry, electrical resistance, X-ray diffraction and transmission electron microscopy to detect the “true” temperature onset of the R-phase.

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The amorphous Fe₄₀Ni₄₀B₂₀ alloy shows excellent soft magnetic properties when heat-treated at 630 K for 10–15 min. The improved magnetic softness is attributed to the relaxation of internal stress. The relaxation behaviour obeys the so-called ‘lnt’ kinetics. Small crystalline particles do appear after longer duration isothermal treatment at 630 K which is much lower than the crystallization temperature. Formation of crystalline particles induces magnetocrystalline anisotropy in the system which in turn detoriorates the magnetic softness.

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In order to obtain the diffusion coefficient of hydrogen in iron free from trapping by dislocations and impurities, electrochemical permeation measurements have been done using high purity iron (99.99 mass% Fe), pure iron (99.99 mass% Fe, high substitutional and low interstitial impurity contents), pure iron (99.94 mass% Fe), and commercially pure iron (99.83 mass% Fe) between 278 and 318 K. Though these specimens, in which the dislocation densities are (0.6–4.4)×10¹¹ m⁻², have been annealed at high temperatures (973–1223 K), the diffusion coefficients measured (D_a) are influenced by the trapping effect of dislocations. Therefore, the diffusion coefficients free from dislocation trapping (D_df), and free from dislocation and impurity trapping (D_H) have been calculated from D_a on the basis of the trapping theory. In the iron specimens of 99.99 mass% purity, the values of D_H are nearly equal to those of D_df. This indicates that D_a obtained in the 99.99 mass% purity iron specimens is little influenced by the impurity atoms. The temperature dependence of D_H has been determined as follows:
D_H(m²⁄s)=(5.8±0.1)×10⁻⁸exp(−(4.5±0.2)(kJ/mol)⁄RT).

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High temperature heat contents of the II–VI and IV–VI compounds (II: Zn, Cd IV: Sn, Pb VI: Se, Te) were measured over the temperature range of 700–1550 K using a drop calorimeter. The heat of α-β transformation of SnSe was 1.1±0.1 kJ/mol at 788±2 K, and the heat of fusion of CdSe, CdTe, SnSe, PbSe, SnTe and PbTe were 44.8±0.2, 43.5±0.3, 35.5±0.4, 42.3±0.4, 39.5±0.3 and 47.6±0.4 kJ/mol, respectively, at the corresponding melting points of 1521±3, 1373±3, 1149±2, 1351±2, 1080±3 and 1209±2 K. The heat contents and heat capacity equations were derived using the Shomate function for the solid compounds and the least square method for liquid phases. Based on the third law method, the Gibbs free energies of formation were determined from the obtained heat capacity data.

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Amorphous Mg₈₅Y₁₀Cu₅ powders with a particle size fraction less than 25 μm were produced by using a newly designed high-pressure argon atomization-consolidation equipment in which each content of oxygen and moisture was controlled to be less than 1 ppm. The extrusion of the amorphous powders at 373 K causes the formation of a bulk alloy having the nonequilibrium structure which is the same as that for the as-atomized powders. The thermal stability of the extruded alloy is also the same as that for the as-atomized powders. The Young’s modulus, compressive fracture strength and fracture elongation at R.T. for the bulk alloy are 46 GPa, 750 MPa and 1.8%, respectively, which are nearly the same as those for the melt-spun amorphous ribbon with the same alloy composition. The fracture surface of the bulk alloy consists mainly of a vein pattern. No appreciable trace of the original boundaries between the powders is seen and hence the powders seem to have a truely bonding state. The good consolidation tendency is presumably because of the clean surface state for the atomized powder by the use of the closed preparation equipment.

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The metalorganic chemical vapor deposition of CdTe on (100) oriented GaAs was performed under atmospheric pressure. By using a well-designed reactor and controlling total hydrogen flow rate, specular layer was obtained at a temperature range of 613∼713 K. X-ray diffraction and electron microscopy revealed the (111) growth orientation and presence of twins. The photoluminescence measurements indicate that defects and nonradiative recombination centers increase with departure from the optimum hydrogen flow rate of 1000 sccm. The optimum growth condition corresponds to that of uniform deposition rate calculated on the basis of flow dynamics.

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The thermal magnetic analysis and the temperature dependence of the permanent magnet properties of CoPt, Fe–39Pt and Cr–59.2Pt alloys were investigated by using a VSM and a recording fluxmeter.
The results of the thermal magnetic analysis showed that the magnetization of these alloys have the maxima at 720 K (Co–Pt), 650 K (Fe–Pt) and 1085 K (Cr–Pt). It is considered that the maximum appears to be due to the Hopkinson effect by the rapid decrease of the magnetic anisotropy near Curie temperature.
The coercivities are 820 kA/m for the CoPt, 520 kA/m for Fe–39Pt and 700 kA/m for Cr–59.2Pt alloys at 4.2 K, and decreased gradually with increasing temperature. The temperature coefficients of residual flux density are −0.04%/deg for CoPt and −0.06%/deg for Fe–39Pt alloys.
The Cr–Pt magnet alloys, which show a high coercivity in a narrow composition range from 58 to 60 at%Pt, exhibit a low magnetization but a high magnetic transition temperature. It is presumed that the mechanism of the coercivity is closely related with the enhanced magnetization, because the coercivity increase with increasing magnetization.

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An icosahedral (I) single phase with magnetization at room temperature (RT) has been found to form in a sheet with a thickness of 0.5 mm for an Al₆₄Pd₁₅Mn₁₅B₆ alloy prepared by casting its molten alloy into a copper mold and then annealing for 360 ks at 650 K. The as-cast alloy consists of an I-phase containing a small amount of the cubic AlPd (β) phase and the subsequent annealing at 650 K causes the formation of the single I-phase and the disappearance of the β phase. The further increase in annealing temperature results in the transition to equilibrium crystalline phases accompanying the disappearance of the magnetization. The magnetization in a field of 1.59 MA/m at RT is 1.00×10⁻⁵ Wb·m/kg in the as-cast state. It increases gradually with increasing annealing temperature, shows a maximum of 1.26×10⁻⁵ Wb·m/kg at 650 K and then disappears by the exhaust of B from the I-phase saturated with B before the completion to equilibrium crystalline phases. The finding that the magnetic I-phase is obtained in the bulky Al–Pd–Mn–B alloy by the simple process of casting and annealing is important in the subsequent development of ferromagnetic I-alloys.

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