The diffraction theory evolved by Matsubara, Kanzaki and Krivoglaz for solid solutions has been extended so that it may be applied to thermal diffuse scattering (TDS) from an ordered phase. The TDS intensity is calculated by using the extended theory on a β-brass (Cu–47.5 at%Zn), which shows strong diffuse streaks along the 110 rel. direction in X-ray diffraction patterns taken at room temperature. As a result, the diffuse streaks are shown to occur primarily by the soft TA2 phonon mode in the B2 type ordered lattice of the β-brass. Intensity measurements of diffuse streaks have also been made by using a single crystal of the β-brass. On subtraction of the calculated TDS intensity from the measured one, solute-lattice coupling parameters are obtained to the third neighbor of atoms. From the solute-lattice coupling parameters, three elastic constants, c₁₁, c₁₂ and c₄₄, of the β-brass are estimated, and they are in good agreement with those obtained by an ultrasonic method.

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Static flow stress decreases abruptly when ultrasonic oscillatory stress (17.8 kHz) is intermittently superposed. The decrement in static flow stress, Δσ, was measured in an Al–5 at%Mg alloy. Ranges of strain rate and testing temperature were from 1×10⁻⁴ to 1×10⁻³ s⁻¹ and from 473 to 673 K, respectively. Δσ at 673 K was zero irrespective of superposed oscillatory stress amplitudes. This implies that the dislocation velocity at 673 K is proportional to the effective stress. Δσ’s at 473 and 573 K were dependent on oscillatory stress amplitudes, strain rates and testing temperatures. These experimental results indicate that the dislocation velocity-effective stress exponent, m^∗, is greater than unity at lower temperatures. The change in m^∗ with temperature and strain rate is satisfactorily explained in terms of a solute-dislocation interaction.

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Acoustic emission during yielding of a dispersion hardened alloy has been estimated on the basis of dislocation movement through a random array of obstacles, using a computer simulation.
The estimated acoustic event count rate takes a maximum at a stress σ_AE during yielding. For the case of the same obstacle-strength, this stress σ_AE is proportional to the reciprocal of average distance between the obstacles. The acoustic peak event count is proportional to the stress σ_AE. The stress is roughly a half of stress σ_e, which was calculated by Foreman and Makin, over the full range of the obstacle strength. With increasing obstacle strength, the estimated acoustic event count during yielding increases at first, and decreases finally.
When obstacles with two differing strengths coexist, the acoustic event count rate during yielding takes a maximum at a lower stress.
These estimations are compared with the experimental results for a dispersion hardened alloy reported before.

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Using, iron, Fe–12%Ni alloy and Fe–20%Ni alloy, the corrosion behavior in hydrogen chloride gas containing 0–75 vol% oxygen at temperatures between 523 and 973 K has been investigated by means of a thermogravimetric technique and by measuring the mass loss and the amount of sublimates. In pure hydrogen chloride gas, the corrosion rate was determined by the formation and sublimation of divalent chlorides of iron and nickel. Up to 673 K, a nearly parabolic scale growth was observed, and addition of nickel to iron suppressed the rates of the corrosion and scale formation. When the temperature exceeded 773 K, sublimation of the corrosion products occurred violently in hydrogen chloride gas, regardless of alloy composition, and hence the corrosion rate was independent of alloy composition. Addition of oxygen to hydrogen chloride gas greatly accelerated corrosion due to the formation and sublimation of a low melting point volatile ferric chloride by oxychlorination.

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A superconducting amorphous phase with high strength and good ductility has been found in rapidly quenched alloys of the Zr–Nb–Ge system. The amorphous phase was formed in a wide composition range from 0 to 65 at%Nb and from 11 to 21 at%Ge. All the amorphous alloys showed a superconducting transition whose temperature, T_c, increased from 2.59 to 3.38 K with increasing Nb content and with decreasing Ge content. The upper critical magnetic field and critical current density for a Zr₄₅Nb₄₀Ge₁₅ alloy were of the order of 2.47×10⁶ Am⁻¹ and 2.40×10⁶ Am⁻², respectively, at 1.70 K in the absence of applied field. The upper critical field gradient at T_c, −(dH_c2⁄dT)_Tc, and the electrical resistivity at 4.2 K, ρ_n, decreased from 2.29×10⁶ to 1.31×10⁶ Am⁻¹ K⁻¹ and 2.70 to 2.00 μΩm, respectively with the amount of Nb. The GL parameter κ and the GL coherence length ξ_GL(0) were estimated to be 64–101 and about 8.2 nm, respectively, from the experimental values of (dH_c2⁄dT)_Tc and ρ_n by using the GLAG theory, and hence it is concluded that the Zr–Nb–Ge amorphous alloys are extremely “dirty” type-II superconductor having very weak flux pinning force.

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The influence of rapid solidification on aging of a Cu–2.1 mass% Be–0.2 mass% Co alloy has been investigated by means of hardness tests, X-ray diffraction and electron microscope observation. Rapid solidification (R.S.) induces small maximum hardness and prolonges the time to attain the maximum hardness in contrast to our former results on Cu–Ti and Ni–Ti alloys. The dominant factor of age-hardening of the R.S. alloy is dispersion of fine γ phase particles instead of coherent γ^′ phase in the commercially produced (C.P.) alloy. Transformation modes are about one for the R.S. alloy and about two for the C.P. alloy. The isothermal transformation rate of the R.S. alloy is lower than that of the C.P. alloy below 750 K . This difference is explained by preferential fine precipitation of γ phase instead of γ^′ phase. The isothermal transformation rate of the R.S. alloy is higher than that of the C.P. alloy at aging temperatures above 750 K . This result is in good agreement with our former results on Cu–Ti and Ni–Ti alloys.

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Commercially pure Fe, Fe–Si, Fe–Cr, Fe–Ni, Fe–Mn, Fe–Cu and Fe–C alloys were dipped into molten aluminium (99.8 mass% Al) at 973, 1023 and 1073 K for various times. The alloy layers formed were examined by X-ray and EPMA analysis, and the hardness and thickness of the alloy layers were also measured. The alloy layer formed on each ferrous alloy is mainly composed of FeAl₃ and Fe₂Al₅, and much FeAl₃ is near the adhering aluminium and no FeAl₃ near the base metal. Fe₂Al₅ occupies the major portion of the alloy layer. For commercially pure Fe, Fe–Si, Fe–Cr, Fe–Ni and Fe–Mn alloys, the Fe–Al solid-solution exists inside the Fe₂Al₅ layer. The alloying elements in the base metal, especially Si, Ni and Cu, reduce the thickness of the alloy layers. The alloy layers formed on commercially pure Fe, Fe–Ni, Fe–Cr, Fe–Si, Fe–Mn and Fe–Cu alloys are tongue-like and that formed on Fe–C alloy is band-like. In the latter, however, a slightly tongue-like shape appears at a lower temperatue. The hardness of each alloy layer near the base metal is higher than that near the adhering aluminium. The alloy layer formed on the Fe–C alloy is slightly harder than that on the other alloys.

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The annealing textures in polycrystalline aggregates of pure iron and iron-silicon alloys do not coincide, in some cases, with a synthesis of textures in single crystals having various initial orientations. This discrepancy suggests that initial grain boundaries have an effect on the texture formation of polycrystalline materials. This effect has been investigated by using pure iron with various initial grain sizes. Results obtained are as follows. During cold rolling, the neighbourhood of initial grain boundaries in pure iron tends to become {111} regions with a high density of dislocations. In the course of subsequent annealing, preferential nucleation of {111} recrystallized grains takes place in the initial grain boundary region. Because of this effect, a smaller initial grain size results in a higher density of the {111} component in the annealing texture. The recrystallization process in which {111} nuclei grow into {112} and {113} matrices, plays an important role in the {111} annealing texture formation of pure iron.

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