Rolling and recrystallization textures of Al-1 wt% Mn alloy single crystal with (123)[41\bar2] as the initial orientation were investigated after 90% cold rolling and annealing at various temperatures. A homogeneous rolling texture with the principal orientation of (167)[92\bar3] was obtained. At 653 K where the competition between recrystallization and precipitation occurs, recrystallized grains whose orientations were determined by micro Laue method have the same orientation as the deformed matrix. The formation of these recrystallized grains are considered to be a result of recrystallization in situ. Annealing at temperatures above 673 K where recrystallization precedes precipitation leads to the generation of a number of orientations as (476)[\bar22\bar1], (123)[4\bar52], (739)[12\bar19], (437)[\bar704] and (011)[6\bar11], all of which are related to the deformed matrix by rotations around ⟨111⟩ axes. These orientations result from selective growth owing to the existence of Mn and a small amount of Fe in the solid solution state.

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The interdiffusion coefficients, \ ildeD, in the Ni–Mn binary alloy system have been determined by the Boltzmann-Matano method in the temperature range between 1073 and 1323 K for various couples consisting of pure nickel and Ni-(10∼40) at% Mn alloys. Logarithm of \ ildeD increased linearly with the manganese content up to 35 at% Mn which was the upper limit of this experiment, while the activation energies and the frequency factors for interdiffusion decreased monotonously with manganese content. On the other hand, the intrinsic diffusion coefficients, D_Mn and D_Ni, have been determined mainly by using Darken’s relation, showing that the diffusion of manganese atoms was twice or three times as fast as that of nickel atoms at the chemical composition of 19.7±0.4 at% Mn. Furthermore, the intrinsic diffusion coefficients, D_Mn and D_Ni, have been determined by using Dayananda’s thermodynamical analysis, showing that the results were smaller than those obtained by Darken’s analysis. Atomic mobilities, G_i, were also calculated from Dayananda’s method; G_Mn was twice or three times larger than G_Ni at the temperature range between 1173 and 1323 K.

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The nature and the causes of the banded structure appearing in the eutectic Al–Si alloy were investigated by optical and scanning electron microscopy and by X-ray microprobe analysis.
The banded structure may be classified into two groups: The first group is due to an abrupt change of the solidification rate in an insulated mold. This band must be formed by the concentration variation due to sudden changes in growth rate.
The second group is due to the local segregation of a ternary element such as sodium, when it is added to a binary eutectic system.
The formation of the banded structure is governed by the solidification rate, temperature gradient at the solid-liquid interface and the build-up of the liquid layer rich in the ternary additions rejected from the eutectic solid. If the solidification condition is proper, the formation of the banded structure can be avoided even when the sodium content is in excess.

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The segregation behavior of sulfur, oxygen and phosphorus at the (100) surface of the iron single crystal, the bulk sulfur concentration of which had been adjusted to 23∼66 mass ppm, was investigated by using AES-LEED from the segregation kinetic point of view.
When the specimen was annealed between 973 K and 1123 K in vacuum, sulfur, oxygen and phosphorus initially segregated to the surface. As the annealing was prolonged, however, the concentration of sulfur at the surface increased, and at first phosphorus and then oxygen disappeared from the surface. So finally only sulfur existed at the surface.
This phenomenon can be explained as follows. At the first stage, sulfur, oxygen and phosphorus occupy surface sites simultaneously. The surface activities of these elements, however, are in the order of sulfur>oxygen>phosphorus. Therefore, as the concentration of sulfur at the surface increases, sulfur replaces first phosphorus and then oxygen. Finally, only sulfur occupies the surface sites.
The concentration of sulfur at the surface increased in proportion to the annealing time and then reached a constant value. The segregation rate became greater as the bulk sulfur concentration increased.
The activation energy of the segregation rate increased as the bulk sulfur concentration decreased. This is because sulfur is trapped by the impurities such as manganese and magnesium which have strong affinity for sulfur and this effect becomes more remarkable as the bulk sulfur concentration decreases.
When the concentration of sulfur at the surface reached an equilibrium value, the structure of the surface was c(2×2) and two iron atoms combined with one sulfur atom at the surface.

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The crushing strength of the metallised iron pellets of original basicities ranging from 0.64 to 2.54 was tested at room temperature after hydrogen reduction at temperatures between 973 and 1273 K.
The slag phase in the lowest basicity pellet is mainly calcium silicate. As its strength decreases remarkably with an increase in temperature, the degree of swelling increases correspondingly. Consequently, the crushing strength of the pellet decreases as the reduction temperature rises.
On the contrary, the amount of calcium ferrite in the slag phase prevails as the basicity increases.
As the strength of calcium ferrite decreases very gradually with an increase in temperature, the degree of swelling varies slightly with it for the pellets of high basicities.
However, the crushing strength of the pellets is unexpectedly low despite their small degrees of swelling, because the partial disintegration of the iron particles is enhanced even at relatively low temperatures as the basicity increases.
A hypothetical correlation between the crushing strength and the isothermal reduction temperature was presented, with the influences of the degree of maximum swelling, the partial disintegration of the iron particles in the pellet and the sintering of iron particles during later periods of reduction at higher temperatures taken into consideration.

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Stability of a planar solid-liquid interface was metallographically examined in Al–Zn alloys which had been quenched in the course of unidirectional solidification. Instability of the planar interface occurred in the condition predicted by the linear perturbation analysis.
The measurements of the Zn distribution in the liquid in contact with the planar interface after quenching gave the diffusion coefficient of Zn in liquid Al and the partition coefficient of Zn in solid to liquid.

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Interfacial morphology at the beginning of the instability of planar solid-liquid interface was observed in Al–Zn alloys after quenching specimens during the unidirectional solidification. Interfacial holes occured at the beginning of the instability which were distributed regularly or irregularly depending on the growth condition of crystal as predicted by the theory. In the case of the regular distribution of the holes, the reasonable interfacial energy between solid and liquid was obtained comparing with the theory but in the irregular case it was erroneous.

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