The effect of Cr₂O₃ addition on magnetic resonance in amorphous slags containing iron oxides has been studied. At room temperature single exchange-narrowed lines with g∼2 have been observed for both the slags with free and 0.1 mol% Cr₂O₃. The lines for the Cr₂O₃-doped slag are fairly broader than those for the undoped one. As the temperature is lowered, the linewidths for both slags increase monotonously and reach the nearly same values at about 65 K, and below the temperature they are almost independent of temperature. The positions of the lines shift towards lower fields with decreasing temperature. The temperature dependences for the two slags fairly differ above about 65 K but below the temperature they are very close to each other. Below about 25 K the lines move rapidly to higher fields with decreasing temperature and new lines appear at lower fields. For the slag with 1.0 mol% Cr₂O₃ no ESR absorption has been observed in the condition of the present work. These experimental results are understood by taking account of the enhancement of local crystallization of iron oxides by the doping of Cr₂O₃.

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Ratios of the intrinsic diffusion coefficients relative to the number of mole fixed frame of reference in the α phase of Ag–Cd alloys at 1073 K and Ag–Zn alloys at 1023 K have been determined by vapor-thin plate method. Although the method is only applicable to a system in which one of the components has high vapor pressure in contrast with negligible vapor pressure of the other component, the ratios of the intrinsic diffusivities can be determined easily and precisely at desired compositions without requirement of concentration-penetration profiles and laborious examinations of the marker shifts. The ratio of the intrinsic diffusivities, D_Zn^N⁄D_Ag^N, in the concentration range between 2.2 and 13.7 at%Zn increases from 1.3 to 2.5 with increasing Zn concentration. The ratio, D_Cd^N⁄D_Ag^N, in the range between 2.5 and 13 at%Cd is almost constant to be 1.3.

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The constitutive behaviour of Al-5% Si alloy has been studied in the temperature range 500–800 K and in the strain rate range 0.02–200 s⁻¹ in view of obtaining flow stress data and evaluating the mechanism of hot deformation. For this purpose, hot compression tests have been conducted on cylindrical specimens of the alloy. From the transient measurements of force, ram travel and temperature changes during deformation, the values of flow stress, true strain and strain rate have been calculated. The kinetics of deformation has been described using standard kinetic rate equations. An apparent activation energy of 130 kJ/mol and an apparent activation volume in the range 10–200 b³ have been evaluated from the temperature and strain rate dependences of flow stress. It is suggested that at high temperatures and strain rates, the deformation takes place by cross-slip of screw dislocations.

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The yield stress, tensile strength and ductility of hypo-eutectoid graphitic steels are given as functions of microstructural factors such as the ferritic grain size d_F, volume fraction of graphite f, mean graphite nodule diameter d_G, and mean ferrite path between graphite nodules λ.
The graphitic steel in which graphite nodules have formed at ferrite grain boundaries exhibits a sharp yield point, and the yield stress can be expressed by a function of two factors d_F^−1⁄2 and λ^−0.22. The steel containing a number of graphite nodules inside the ferrite grains shows no yield point, and the 0.2% proof stress is nearly constant independent of f, d_F, d_G and λ.
The tensile strength of the graphitic steel increases linearly with d_F^−1⁄2, but decreases slightly with increasing d_G.
The ductile fracture strain is given by a function of lnd_G and lnλ, or of ln[(1−f)⁄f] according to a multiple regression analysis. It is concluded that the ductility of the graphitic steel depends strongly both on d_G and λ, or on the volume fraction of graphite.

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The effects of cooling rate after β annealing on cryogenic temperature mechanical properties were investigated for normal- and ELI-grade Ti–6Al–4V alloys. The β-annealing was very feasible method to improve cryogenic temperature fracture toughness. The slowly cooled β-annealing, in particular, brought about excellent fracture toughness and good fracture strain with a slight loss in strengths at 4 K. For the slowly cooled specimens, the single oriented α plates formed a packet smaller than prior-β grain. The high fracture toughness is attributed to the frequent arrest and deviation of the crack at the packet boundaries.

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Yield stress of aged Al-11.1 mol%Li alloy was measured at temperatures between 77 and 523 K, and the deformation induced dislocation structure was examined by transmission electron microscopy. Strength and dislocation arrangements depend largely both on the aging condition and on the testing temperature. The peak positions in strength vs aging time curves shift to the side of shorter aging time with increasing testing temperature. The mode of interaction between dislocations and δ′-precipitates also varies with the testing temperature. For the specimens aged nearly to the peak strength, the positive temperature dependence of yield stress is observed in the temperature range in which dislocations move in pairs cutting the δ′-precipitates. In the over-aged specimens, dislocations by-pass the precipitates leaving dislocation loops around the precipitates at the beginning of plastic deformation. The shift of peak positions in the aging curves and the variation of the interaction modes between dislocations and precipitates with testing temperature are explained in terms of the positive temperature dependence of cutting stress and the negative temperature dependence of by-passing stress.

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In order to investigate the origin of internal stress in a solution-hardened temperatures, the internal stress and dislocation density have been simultaneously determined by a stress change test during creep deformation of Al-5.7 at%Mg alloy in a temperature range 573–673 K and a stress range 4.5–40 MPa.
It is found that a unique relation,
\barσ_i=0.37Gb\sqrtρ,
holds whether the creep is in a steady state or not, where \barσ_i is the internal stress, ρ the dislocation density, G the shear modulus and b the magnitude of the Burgers vector. From the relation, it is concluded that the origin of internal stress is the long range stress field of forest dislocations.

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The oxidation behavior of Ni–20Cr–5Al alloys containing 0.01, 0.04 and 0.40 mass% cerium was studied in air at 1473 K for periods up to 720 ks by mass-change measurements, X-ray diffraction, scanning electron microscopy and electron probe microanalysis. The mass gain slightly decreased in a 0.01% Ce alloy, and increased in 0.04%Ce and 0.40%Ce alloys. The surface oxides on a Ce-free alloy and 0.01%Ce and 0.04%Ce alloys were predominantly α-Al₂O₃. The major surface oxides on a 0.40%Ce alloy were α-Al₂O₃ and NiAl₂O₄ with small quantities of rod-shaped CeO₂. The surface oxides on a Ce-free alloy and 0.01%Ce and 0.04%Ce alloys spalled during cooling. No spalling of the surface oxides occurred in the 0.40%Ce alloy in any of the oxidation conditions studied. The oxide/alloy interfaces of the Ce-free alloy and the 0.01%Ce and 0.04%Ce alloys were fairly smooth. On the other hand, α-Al₂O₃ and rod-shaped CeO₂ in the 0.40%Ce alloy protruded from the surface. The improvement of the oxide adherence of the alloy was attributed to the protrusion of the surface oxide into the alloy substrate.

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The melt spinning of Pb–Sn–Ge alloys with Pyrex glass was investigated as a means of producing a high temperature superconducting filament. Long filaments with T_c higher than 8.5 K of Pb_100-x-ySn_xGe_y (x≤30, y≤36) alloy were obtained from the molten state at 1500 K with a winding speed of 2.63 m/s. The filament was 20×10⁻⁶ m in diameter and had a mixed structure of lead (fcc) and germanium (diamond) phases. The germanium, lead and tin elements are homogeneously distributed in the filament.
In spite of such a hard heating treatment as heating at 673 K for 1800 s, the Pb₅₂Sn₂₀Ge₂₈ filament annealed exhibited the superconductivity with high T_c of 8.4 K and was found to be fine polycrystalline with a grain size of 2000×10⁻¹⁰ m and a ductile material with tensile strength of 54 MPa and elongation of 1.8%.

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