The orientations of the new grains formed upon the spontaneous recrystallization of single crystals of extended aluminium has been studied. When the tensile strain was lower than 30 pct., the grains having random orientations were observed. While it was found that upon recrystallizing specimens of about 50 pct. elongation, the new grains were related to the parent by approximately 20 and 40 degrees rotations about common [111] axis.
However, the rotations occurred in one direction only about the pole of the latent slip plane, but about no others. Futhermore, the grains having a preferred orientation showed fine substructures. It has been discussed that the mobility of the grains were related to the strained matrix by the 40 degree rotation about [111] axis may be affected by the distributions of dislocations after deformation by primary and conjugate slip, and that the present results can be accounted for solely on the basis of the orientation dependence of the growth rate of the growing grain into the matrix.

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The experiment was made for getting the directional property away from rolled aluminium sheets. The specimens were prepared from a c. c. p. ingot of 99.48%, with the thickness after scalped of 145mm.
The directional property was examined mostly through cupping test, mechanical test and etching test, by use of 27 kinds of aluminium sheets rolled by defferent methods, as shown in Table No. 1.
The results of the experiment are summarized as follows:
(1) In the case of hard and 1/2 hard sheets, the earing height appears in accordance with the degree of cold reduction, while in the case of annealed sheet, the earling height is least when it is worked to the exteut of by cold reduction.
(2) In the case of annealed sheet, most of the pits are of (100) and (110), many pits, a side of which points the direction of 45° against the rolling direction, are found in the sheets in which the earing height shows the angle of 45° against the rolling direction. Similarly, many pits, a side of which points the direction of 0° or 90° against the rolling direction, are found in the sheets in which the earing height shows the angle of 0°∼90° against the rolling direction.
The directional property can thus be examined.

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The work-hardening of Al-Mg alloys (2-7 pct. Mg) at low temperature is not so dependent on temperature as pure aluminium, but is the material is deformed with creep at -196°C.
The recovery of stress, hardness, and electrical resistance of cold-worked Al-Mg alloys, and its recrystallization process have been investigated. The electrical resistance is recovered with the activation energy of 0.34eV between 0°C and 100°C. The stress is recovered rapidly between 100°C and 200°C, and the activation energy is 1.10-1.25eV with the increase of Mg content.
The recrystallization process seems to depend on Mg content and deformation temperature.

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The mechanical properties of die-castings, the effects of casting conditions upon these, and the relation between the microstructure and the strength of the products have been studied. The results are summarized as follows.
1. The mechanical properties of the die-cast tensile specimens were sensitively affected by the casting temperature, but not by the die-temperature.
2. The injection pressure affects upon the mechanical properties. A sufficiently high pressure is needed for improving the strength.
3. The proof stress at 0.2 percent offset of the silumin die-cast tensile specimens lies almost within the range between 12 and 14kg/mm², and was nearly constant regardress of the tensile strength when its strength was above 17kg/mm².
4. The average elongation in 50mm of the above-mentioned specimens was 2.8% for the nominal tensile strength (24.5kg/mm² of ASTM), which was lower than the nominal value.
5. The relation between the microstructure and the mechanical properties of the die-cast automobile parts were examined, but the difference of strength which depended on the micro-structures could not exactly be decided.
6. The roughness of surface of the die-casting and the die cavity was tested. It is considered from these tests that the roughness of surface of the davity is propertional to numbers of shot.

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Various methods are used to produce chemically oxidized films on the surface of aluminium and aluminium alloy sheets. All these films, have some extent of luster and their own particular color. Recently, with the use of more aluminium for building materials, demands for luster-less sheets have increased. The method of producing anti-glare film on aluminium sheets by use of Na₂SiF₆ as the main chemical agent shows good results with 2S sheet. However, in the case of this method being applied to 52S sheet, it is sometimes difficult to obtain a satisfactory film, and there seems to be room for improvement on giving the color and mechanical strength to the film.
With emphasis on producing the color luster and mechanical strength to meet the requirement for building material, this study is to try to bind out the method to obtain a silver colored film by means of an improved chemical bath with other additional chemicals than Na₂SiF₆.
In this first report, from the results of various preliminary tests, the effects of the treatment conditions of the bath using such additions as H₃BO₃, NaBF₄, NH₄ClO₄, BaF₂, CaF₂, and Ca₃(PO₄)₂ to the luster, Marten's scratching hardness, weathering resistance, and chemical resistance were made clear, and the optimum condition for forming an anti-glare film with less luster than those obtained by the conventional methods was established.

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(1) In the case of anodical electrolysis under a constant electric current at vorious current densities, the conditions for obtaining the electro-polished bright surface are in such range that bath voltage becomes higher as the current density gets larger, and with the increase in electrolysis time, bath voltage becomes higher.
(2) Effect of number of vibration of anode on the bath voltage.
A. In the case of the current density under which unevenly electro-polished surface (CR) is obtained under statical method, the following phenomenon appears with the increase in numbers of vibration.
(CR) decrease in bath voltage → (CS) decrease in b. V. (smoothly polished surface) → etched surface
B. In the case of the current density under which scorched surface (D) and ragged surface (E) is produced, the following phenomenon appears, with the increase in numbers of vibration:
(D) and (E) increase in b. volt. → (CS) decrease in b. volt → uncompletely polished surface.
(3) As a consideration on the process of electro-polishing, etching phenomenon stops with the growth of anodic film.
The film appears and then, in the next instance, dissolved into hot electrolyte. This action works as electro-polishing. The over-dissolution of film, however, makes ragged and scorched surface.

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The curves formed by the relation between current density and bath voltage in electro-polishing operation can be classified into following five ranges.
AB: The range in which etched surface (A) is produced.
BB'&B'C or BC: The range in which uncompletely polished or polished surface is produced. (BC is produced mainly by vibration method.
When numbers of vibration of anode are raised to 60 r. p. m. or more, gas produced by electrolysis can not stay on the surface of anode and temperature of the adjacent layer to the overall surface is kept in equality. The smoothly polished surface is thus obtained.
CD, DE: The range in which ragged surface and scorched surface are produced.
The current density at the point B becomed higher, in accordancewith the increase in bath temperature and in numbers of vibration of anode. These phenomena are considered to be due to the in crease in the dissolving velosity of anode film into electrolyte.

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Corrosion tests for aluminium alloys of 1S, 2S, 3S and 52S which are normally used as anti-corrosion materials, are made in red dry wine, to examine their anti-corrosion property. This is to report the outline of the tests.
The aluminium alloys are extensively attacked by red wine, and the reactions are very quick compaired with those in white dry wine which has nearly equal normal contents of alcohol and acidity with red one. It seams therefore, that it is impossible to utrilige these alloys in practice unless some special treatments such as surface treatment on alloys, or putting some agent in wine are made.
It is from the test that the total acidity in wine decreases slightly (but it is not so clear) regardless of the time of dipping alloys, pH-value of wine increases its tannin content decreases, colour of wine fades, and its flavor and teste are deteriorated.

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Anti-corrosion properties of aluminium alloys such as 1S, 2S, 3S and 52S, which are generally used as anti-corrosive materials, were examined by use of such wines an brandy, baking sherry, white and red dry wine.
It was found that each of them was more or less attacked by wines. The corrosion was especially appeared when the brandy was used and the palate and flavour of the brandy was remarkably made worse. The conclusion was thus made that aluminium alloys are not adequate to be utelized in wine industry at lest under present circumstance.
This is to report on the charactaristics of corrosion resistance of aluminium alloys in sumary and the proposed counter-plan of how to utilize these alloys in wine andbrandy industries.

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The corrosion resistance against wines was studied in previous reports on aluminium alloys such as 1S, 2S, 3S and 52S, which were generally used as anti-corrosion materials, and it was found that these alloys were so easily attacked by wines that they could be used little in wine and brandy industries.
This is to report the result of a study on a new method for giving the anti-corrosion effectt to aluminium alloys by means of adding an agent to brandy for sealing up the reaction by brandy to the major contents of the alloys.
As the agents, several sorts of condensed posphate were tried to use. Of these agents, the one consisting of hexametasodium, as main content, phyrometasodium and tripolysodium gave the remarkable anti-corrosion effect to be alloys and, in addition, it even made the palate and favour of brandy better.

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