Heating tests of various sodalite compounds synthesized in the liquid phase were carried out by the thermobalance and the differential thermal analysis, and the change in crystal structure was traced by X-ray diffraction and chemical analysis in the region of temperature where change in thermogravimetry and endo-thermic orexo-thermic reaction appeared.
The findings are as follows:
(1) A greater part of the water in crystal was removed in every sample at 100-250°C. This water is as zeolitic water, the structure of which is not changed in this way of dehydration.
(2) The sodalite eventually changed into carnegieite after dehydration, though the transition temperature is different depending on the kind. In this process, some of them change directly into carnegieite while other through the nepheline.
The formers are the zeolitic compounds, sulfate sodalite and chloride sodalite, while the latters are hydroxy sodalite, carbonate sodalite and nitrate sodalite.

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This is to report on the study of the effects of homogenization of ingot and extrusion conditions to the properties of extruded products of Al-Mg-Si ternary alloy.
The findings are as follows:
1) The effect of the homogenization treatment to the properties of the extrusion products is dependent on the weight ratio of Mg: Si, in the region of balanced Mg₂Si and excess-Si, the influence by the homogenization treatment to the various properties of products extruded under higher temperature is more than those extruded under lower temperature, while in the excess-Mg region such relation is completely reversed.
2) The influence by homogenization treatment of long time heating at the lower temperature, for example 20hrs. at 350°C, to the properties of the extrusion products is less remarkable than that of slow cooling after short time heating at the higher temperature, for example 8hrs, at 520°C. It is considered that, when homogenized at higher temperature, the precipitates segregated in grain boundary and in grains are solved into matrix and dispersed finely and homogeneously during cooling. On the contrary, when the ingot is homogenized for long time at lower temperature, the precipitates segregated in the grain boundary do not solve into matrix, and those in the grains is coagulated. It is difficult, for such precipitates to solve again into matrix even when the ingot is heated up to the extrusion temperature or to the high temperature caused by extrusion operation.
3) In the case of using this kind of alloy for electric conductor, it is experimentally confirmed that the mechanical properties and electric conductivity of the T5 heat-treated products can compare with those of the standard (T6) of 6101 alloy. The further study is necessary, however, for its actual use in the industrial activity.

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The purpose of this research was to make clear the effects of cold-drawing, particularly of medium and heavy cold working, upon the electrical resistivity of metal. Two kinds of commercially pure aluminium, the nominal grades of 99.9% and 99.99% purity were used. The measurements of the electrical resistivity were made at -196°C using the specimen of 1m in length and 1mm in dia.
In the diagram of the relation between the electrical resistivity and the reduction of the section area, the electrical resistivity was, in its maximum at the point of about 40% reduction and in its minimum at 70%. And yet the discrepancy between the maximum and minimum value was small. When the reduction was over 80%, the resistivity increased abruptly. The curves obtained for both grades of aluminium were quite similar.
This research was not a completely quantitative one, because we could not clarify the structural changes of the crystal lattices according to the varied stages of the reduction. Therefor, the explanation for the experimental results was confined to the tentative and qualitative suggestion.

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It is previously known that the anodized film can be naturally and blackly coloured when Al-2%Si alloy material plastic-deformed under a certain special conditions is anodized. This report is concerned in studying this naturally coloured anodized film by electron-microscope and-diffraction.
Results obtained are following.
1. Many fine Si perticles dispersed in anodized film are observed. The state of this perticle dispersion depends mainly upon the extrusion temperature, and the size of Si perticle can be classified to 2 groups, i. e., in one group it is 0.1-0.3μφ and in the other several μφ. It may be convinced that the naturally coloured anodic film is caused by this smaller perticles.
2. By transmission electron-diffraction, it is confirmed that these perticles are a number of single-crystalline silicon with preferred orientation which is [III] ⊥ anodized film surface.

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The hard-spot which often appears on the overflow side of Al alloy pressure die castings, has a chilled Al alloy structure.
The purpose of this report is to explain the mechanism for the occurrence of hard-spots, by examining the structure of the various parts of pressure die castings, under the assumption that there is a close relation between the structure of hard spots and that of die castings, after comparing the microscopic structure of pressure die castings with that of "Isolite" castings.
The results obtained from gravity die castings and this research are as follows:
1. Hard spots appeared again on the remelted and recast products which had previously had hard spots.
2. The microscopic structure of pressure die castings was very subtle with fine contained particles. α-Al crystals were ill balanced to form a unique structure.
3. In 150 times enlarged photographs under a microscope, the structure of die castings was more fine in the nearer part to the overflow side or the other side of the gate, where the components were partially concentrated to form their blocks. When these blocks come out apparently distinct from the other parts, they are called hard spots. In 600 times enlarged microscopic pictures, the particles of the contained elements were also more fine in the nearer part to the overflow side, where the particles of Si were granulated.
The conclusion reached through the above-mentioned results would be as follows:
In the manufacture of pressure die castings with complicated shapes, the molten metal injected into the dies, hits the inside wall of the dies and scatters. The scattered molten metal hits the inside wall and scatters again. The molten metal is cast and solidified in this process of repeated scattering. The components of the alloy which has been cooled down in this process, are segregated as groups by such mechanical actions as centrifugal separation.

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