Measurements of the electrical conductivity, magnetic susceptibility and thermoelectric power in the liquid In–AgInTe₂ system were carried out over wide temperature and composition ranges. A considerable temperature change of the electronic properties in liquid AgInTe₂ decreases gradually up to 66.7 mol%In with the addition of In and it becomes extremely small in the In-rich region more than this composition suggesting that the system is rather metallic. This was also confirmed by the fact that the thermoelectric power changes its sign around this composition and indicates a small value in the In-rich region. On the basis of a strong scattering model the bonding nature of the system is discussed using data of the electrical conductivity and the magnetic susceptibility. The result indicates that liquid AgInTe₂ exhibits a covalentic character as observed in most of the liquid chalcogenides, and an ionic contribution is rather predominant in the stoichiometric composition range of AgIn₃Te₂. Furthermore, the comparison of the degree of electron localization is made between liquid AgIn₃Te₂ and AgTl₃Te₂ from the present and previously reported experimental results.

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Effect of the specimen thickness on the aging of Al-4 and 10 mass%Zn alloys was studied by measuring the electrical resistance and the intensity of small-angle X-ray scattering (SAXS). When the quenching temperature (T_Q) was high, the value of resistance attained at the stage of aging where the change in resistivity ceased virtually was not influenced by the specimen thickness. In the case of low T_Q, the resistance was higher for the thin specimen because of the impoverishment of vacancies. The total amount of GP zones formed decreased with decreasing thickness or T_Q in the case of low T_Q, but did not depend upon the thickness or T_Q in the case of high T_Q. Both the Guinier radius and the Porod radius for the specimen of 0.1 mm thickness were smaller than those for the 0.2 mm thick one when T_Q was low, but they became independent of thickness when T_Q was high. The quenching temperature at which the Guinier radius was maximum, was higher for the 0.1 mm thick specimen than that for the 0.2 mm thick one. These results are discussed from the viewpoint of the diffusion of vacancies to the surface and their annihilation during aging.

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Y₂O₃-partially stabilized zirconia shows various microstructures, for example, twinned, herring-bone, lenticular, domain, tweed, modulated, martensitic tetragonal structures, anti-phase boundaries and short range ordering. In order to interpret the formation mechanisms of these structures, the phase diagram of the ZrO₂–Y₂O₃ system at low Y₂O₃ contents proposed by the present authors was investigated. It was concluded that cubic-tetragonal transformation in ZrO₂ was para-ferroelastic second order transition and that the (cubic+tetragonal) two-phase region in the diagram was regarded as a miscibility gap. From these standpoints, the formation mechanisms of complex microstructures are also discussed.

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The linear intercept length distribution has been calculated with a grain structure model based on the assumption that the grain diameter has a log-normal distribution. The grain shapes of the solids adopted are spherical, cubic and tetrakaidecahedral. Results obtained are as follows.
(1) The linear intercept length distribution is not log normal in every model.
(2) The difference from a log-normal form in the linear intercept length distribution depends on the standard deviation of the logarithm of grain diameter, lnσ_g. The difference tends to decrease with the increment of lnσ_g.
(3) The linear intercept length distribution is influenced by the grain shape.
(4) The calculated results of the linear intercept length distribution in the present model appreciably differ from the experimental results in the actual grain structure. The difference is, however, attributed to the limit of measurability for the linear intercept length in the experiments.

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In order to clarify the deformation mechanism in the transient creep region, the instantaneous plastic strain and the strain rate have been measured by using pure aluminum from a very early stage of transient creep to the steady state. The creep test has been carried out at temperatures from 623 to 823 K under stresses from 0.81 to 6.7 MPa.
It is found that the instantaneous plastic strain does not depend on temperature; it depends exclusively on stress. At a very early stage of transient creep, the Zener-Hollomon parameter, Z, depends strongly on temperature in the lower temperature region (623–723 K), but it is independent of temperature in the higher temperature region (773–823 K). At a later stage, the Z vs strain curves at lower temperatures converge to a single one, which is the same as that in the higher temperature region, and finally comes into the steady-state.
From the temperature-independence, it is concluded that the main part of the instantaneous plastic strain is produced by the athermal motion of dislocations. From the theoretical analysis based on a dislocation-network model, it is inferred that the creep mechanism in the lower temperature region changes from a process, in which the thermally activated glide of some long dislocation links takes part, to the well-known recovery process at an early stage of transient creep.

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The effects of testing temperature and strain rate on the yield stress of an aged Al–Li–Cu–Mg–Zr alloy have been investigated at temperatures between 77 K and 523 K and over the strain rate range of 1.77×10⁻⁴s⁻¹ to 1.77×10⁻²s⁻¹. The deformation-induced dislocation structure was examined by transmission electron microscopy. In the specimens as quenched, under-aged or aged nearly to the peak strength, dislocations move as pairs when the alloy is deformed at 290 K. In the over-aged specimens, dislocations move as single dislocations and tangle during deformation. For the alloy under-aged or aged nearly to its peak strength, the yield stress decreases with increasing testing temperature from 77 K to 290 K, and the positive temperature dependence of yield stress is observed in the temperature range from 290 K to 450 K. Within this temperature range, dislocations move in pairs cutting the δ′-L1₂ ordered particles. The yield stress decreases with increasing testing temperature above 450 K, and dislocations move as single dislocations. The serrated yielding characteristic is observed for specimens as quenched, under-aged and aged nearly to the peak strength. At testing temperatures below 423 K, the yield stress is almost independent of strain rate at peak-aged and over-aged stages. For the under-aged stage, the strain rate dependence of the yield stress is negative at the temperature range within which the positive temperature dependence of yield stress appears. At testing temperatures above 473 K, the yield stress increases linearly with the logarithm of strain rate at any aging stage, and the strain rate dependence increases with increasing testing temperature.

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Passivity breakdown characteristics of Cr steels have been studied by adding chloride ions progressively in sulfuric acid solutions. Effects of holding time at different potentials on the film growth have also been studied by adding a fixed quantity of chloride ions in sulfuric acid solution after a passive layer has been formed. Comparative study of corrosion kinetics has been made for different modes of experimentation. SEM studies have also been done to examine the nature of breakage of passive layers.

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The oxidation behaviors of the austenitic Fe–8.7Al–29.7Mn–1.04C and duplex Fe–10Al–29Mn–0.4C alloys in air at elevated temperatures have been investigated by the X-ray diffraction and metallographic techniques. The results showed that the oxide nodules were formed on the surface of both alloys at 1073 and 1273 K during the early stage of oxidation. These oxide nodules grew and eventually coalesced to form continuous duplex scales. The composition and structure of the duplex scales depended on the oxidation temperature and alloy composition. For the duplex Fe–10Al–29Mn–0.4C alloy oxidized in air at 1073 K for 259.2 ks (72 h), the duplex scales consisted of an outer (FeMn)₂O₃ layer and an inner α-Al₂O₃ layer at the oxide-alloy interface. However, oxidation of the duplex Fe–10Al–29Mn–0.4C alloy at 1273 K for 259.2 ks led to the formation of an external (FeMn)₃O₄ and an inner α-Al₂O₃ layers with some internal oxides precipitated within the austenitic phase. Furthermore, the SEM micrographs showed that the oxide growth pits were formed on the austenitic Fe–8.7Al–29.7Mn–1.04C alloy after exposure in air at 1273 K for 259.2 ks. However, oxide pyramids were observed to grow on this alloy as the temperature was increased to 1473 K.

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