As the continuation of the previous report, some test of large dimension deep drawing was done to find out the correlation with "earing" and "orange-peel" of aluminium sheet having some different ratios of Fe:Si, as this was concidered to be an important factor to determine orientation of the sheet.
The experiment was done with following conditions;
1) Material: 2S aluminium sheets with Fe:Si ratio of 1:1, 1.6:1, 2.6:1 respectively.
2) Soaking: 4 and 8 hours under 520°C, 8 hours under 500°C.
3) Cold rolling: 92% and 90% reduction, in one way only as well as in cross way rolling.
4) Annealing temperature: 1 hour under 330°, 350°, 375°and 400°C respectively.
As a conclusion, it was found that a working condition with which the aluminium sheet without "orange-peel" and less "earing" can be attainable in some extent.
This investigation was done with the fund afforded by Scholarship Committee of the Institute of Light Metal Foundation, for which we are extremly gratefull.

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This report relates to the observation on the effect of magnesium upon age hardening and corrosion resistance of Al-Mg-Si alloys, when the alloy contains excess magnesium to the stoichio metric composition of Mg₂Si.
The following results were obtained:
1) On the effect of heat treatment; excess magnesium acts negatively.
2) But, corrosion resistance increases with excess of magnesium.
3) Comparing with Mg 1.0%, Si 0.6% alloy, mechanical properties and corrosion resistance are noted in fairly increase with the alloy of magnesium 1.5-2.5% and silicon 0.7-0.8%.

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This paper relates to the observation on the effect of zinc upon age-hardening and corrosion resistance of Al-Mg-Si alloys, when the alloy contains excess magnesium to the ratio Mg to Si in the formula of Mg₂Si.
The following results were obtained;
1) On the effect of heat treatment; zinc acts positively and in case of existence of silicon acts more positively.
2) Corrosion resistance is decreased by addition of zinc and more by coexistence of silicon.
3) But, compering with 61S alloy, mechanical properties and corrosion resistance are noted in fairly increase with the alloy of Mg 2%, zinc 1-3% and silicon 0.3-0.5%.

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The present report relates to an experimental results obtained by measurement of solidification procedure of Al-Si alloy (20% Si) by differential thermal analysis. Summerized results are as follows:
(1) In unmodified condition, cooling rate of 3°C/min, T_p=685°C, T_e=572°C, T₁=113°C, T₂=10°C.
(2) In case of Paddition, temperature T_p and T_e rise with P addition increases, but T₂ lowers while T₁ rises.
(3) In case of polytetrafluoroethylene addition to the alloy with the amount of primary Si is refinable, then temperatures T_p, T_e, T₁ and T₂ are nearly the same; T_p=660-670°C, T_e=573°C, T₁=90°C, and T₂=30°C.
(4) In case if P and polytetrafluoroethylene is added in mixture to the alloy with the amount of primary Si crystals are refinable, then the results are the same as (3). In this case T₂ values are higher and T₁ lower than the cases (1) or (2).

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Pistons were made by low-pressure die casting process. Aluminium alloys used for this process were JIS AC8A, AC8B and AC3A. The main defects occurred were gate solidification, misrun, internal defect, surface defect, and various kinds of shrinkage cavity, etc. The causes of defects were investigated except for the gate solidification and misrun. The result was that these defects were closely relevant to the die mold temperature and pouring speed.

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The grain size of magnesium (commercial purity) and Mg-6% Al alloys with small content of beryllium, calcium, strontium and barium was measured. These elements tend to coarsen the grain of magnesium alloys. Furthermore, we studied supercooling phenomenon of the coarse grained specimens, but this showed no clear relation with the grain coarsening.

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The present lecture is intended to introduce the research works done by the various investigators, concerning on the production of aluminium by means of thermal reduction with carbon.
After brief introduction, the possibitily of the reduction of alumina with carbon has been treated theoretically and the energy consumption for the production of crude aluminium has also been illustrated.
In the third section, so-called carbide process invented by E. Grünert has been introduced and the semiindustrial furnaces for the production or for the decomposition of aluminium carbide, which are proposed by the Pechiney-Ugine group, has been described.
In the fourth section, various methods of extraction of aluminium from thermally reduced crude aluminium alloy, ie. method of distillation, method of separation of the liquid phase centrifugally, method of extraction of aluminium using zinc, magnesium, mercury and lead as the solvent, method of extraction of aluminium as aluminium subchloride and method of electrolysis, have been introduced.

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