This is to report on the study of the effect of the small addition of zirconium, iron, copper and cadmium on the mechanical properties and electrical conductivity of Al-Mg-Si ternary alloys with different Mg/Si weight ratio.
The findings are summed up as follows:
(1) The addition of zirconium gives the largest effect of all the additive elements on the increase in strength of Al-Mg-Si alloy asextruded. When the specimens containing zirconium are extruded and treated by the precipitation heat treatment at 230°C for 2 hours, the following mecanical properties and electrical conductivity can be easily obtained
Conductivity; (% IACS at 20°C) 57%
Ultimate tensile strength; 22kg/mm²
Tensile yield strength; 17kg/mm²
(2) By the addition of iron, the strength of as-extruded Al-Mg-Si alloy is slightly increased. But, iron does not give any effect on the enhancement of mechanical properties of the alloy after precipitation heat treatment.
(3) Addition of copper increases the strength of Al-Mg-Si alloy after precipitation heat treatment and the decrease in electirical conductivity is comparatively small.
Only after precipitation treatment, "excess silicon alloy" containing 0.2-0.4% of copper shows the following values of mechanical properties and electrical conductivity: Conductivity; (IACS at 20°C) 58-56%
Ultimate tensile strength 22-25kg/mm²
Tensile yield strength; 17-20kg/mm²
From this experiment, it is found that the Al-Mg-Si alloy containing small amount of copper is quite suitable for electric conductor, if the environment is not so corrosive.
(4) Addition of cadmium increases the mechanical properties of Al-Mg-Si alloy after solution and precipitation heat treatment. But in case the T-5 treatment is given to the metal, such effect is not so remarkable as in the case of the addition of copper.

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This is the study on the effect of the following elements upon the corrosion resistance of super purity aluminium: Bi, Cr, Cu, Fe, Mg, Mn, Sb, Si, and Zn. These elements are added to the super purity aluminium of 99.998% in the range of 0.03-1.1% and the corrosion resistance mainly against IN-HCl is examined.
The findings are as follows:
(1) Binary system: Copper and iron does not affect much until they reach 0.2% and 0.4% respectively. But if exceed the above limits, they decrease the corrosion resistance of the metal. Zinc and silicon affect a little and magnesium does not at all.
(2) Ternary systems:
(i) Al-Cu-Fe. Up to the limit of 0.1% Cu and 0.2% Fe, there is no effect on corrosion resistance of the metal. But when exceed the above limit, they badly give influence to the metal.
(ii) Al-Cu-Si. When Si addition is less than 0.1%, the resistance is better than that of plain Al-Cu alloy. The resistance gets worse when Cu addition is increased.
(iii) Al-Fe-Si. When Fe content is about 0.2%, the corrosion resistance is lowered if Si content is out of the range of 0.15-0.2%. This phenomena has already been pointed out by Mr. Obinata and Mr. Nishikawa. Mechanical properties are more improved by increase in Fe content than that in Si content, but corrosion resistance gets decreased on the contrary. In general, corrosion resistance of Al-Fe-Si alloys is lowered when the alloys containing more silicon in the range of Al-FeAl₃-α(Fe-Si).

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Besides the "earing, " a problem in deep drawing of aluminium sheet is the "orange-peel" of surface, which grows as the result of the grain-growth under recrystallization. It is important, therefore, to find out the conditions under which the aluminium sheet with no "orange-peel" and less "earing" could be produced.
For the purpose of finding out the correlation between the "earing" and "orange-peel, " the large type tests of deep-drawing have been made, under the below-mentioned conditions, by use of the sheets having the different Fe:Si ratio, which is considered to be an important factor of the directionality of sheet:
1. Materials: 2S aluminium sheets with the Fe:Si ratio of 1:1, 1.6:1 and 2.6:1 respectively.
2. Soaking: 2-8 hours under 535°C
3. Cold-rolling: 92% and 90% reduction in one way as well as cross way rolling.
The findings from the above-mentioned tests are summed up as follows: With the increase in the Fe: Si ratio, the "ear" grows more in the 45°-direction against the rolling direction than in the 0°-or 90°-direction, and as the 0°-or 90°-earing increases, the "orange-peel" becomes more remarkable. The soaking conditions, rolling direction and annealing temperature must be controlled so that the 45°-earing may not grow much and also the "orange-peel" may not appear.

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Under the swaging process of 2S (Fe: 0.27%, Si 0.12%) round bar, the variation of hardness in transverse section, micro and macro structure, flow of material, and tensile properties were measured at summarized as follows:
(1) At the initial stage of cold swaging, the surface layer of 20mmφ 2S bar is more worked than the inner part. Hardness in the outer part increases more rapidly them that in the inner part as the swaging process goes.
After 80% reduction, however, the inner part becomes more deformed and hardened than the outer part.
(2) The tensile strength of the specimen gradually increased with increasing of reduction till about 80%, and the increase in strength gets rapid when the reduction goes to about 90% and more.
(3) Softening of cold-swaged 2S takes place at the temperature of 200°C
(4) Macro-and micro-structure and flow of material are also discussed here.

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Hydronalium (aluminium-magnesium alloys) are characterized by high mechanical properties, excellent machinability, and good corrosion resistance. They are, however, among the most difficult alloys to cast because of their high drossing tendency when molten, of the sensitivity to impurities, hence much care is necessary to use magnesium ingot, return scrap, and even virzin aluminium ingot.
The mechanical properties and corrosion resistance of 5 per cent Hydronalium (aluminium-5 per cent magnesium alloy) are rather sensitive to small difference in the chemical composition. The authors discuss in the report the effect of the content of magnesium, manganese and iron on these properties. All the specimens were cast into the permanent mold.
The mechanical properties showed considerable unstability when magnesium is added more than 5 per cent and in case of 4.5 per cent magnesium elongation increases in spite of comparatively lower tensile strength. The hardness is improved as the content of maganese increases and iron does not make a much effect.
Corrosion test was made by submerging the specimens into 3 per cent sodium chloride aqueous solution, city water and rain water in statical state.
Corrosion resistance to sodium chloride aqueous solution was better with 4.6 per cent magnesium alloy than with 5 or 5.4 per cent magnesium alloys improvable to 5.0 or 5.4 per cent magnesium alloy. When submerged into city water, the less magnesium contents was, the less the weight change became. And their, compact film on the surface of the specimens seemed to introduce the good corrosion resistance.

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Properties of the aluminized coating of steel vary with (a) temperature of immersion, (b) time of immersion, (c) composition of aluminium bath, and (d) alloying elements in the base steel. Many reports have so far been published on (a), (b) and (c), but very few on (d). Very little is known, therefore, about the effect of alloying elements in base steel on the properties of coatings.
This is to report on the study about the hardness, thickness and tongue structure of the intermediate layer of aluminized steel.
(1) Alloy steels containing silicon or chromium; chromium and nickel; chromium and molybdenum; chromium, nickel and molybdenum; chromium, molybdenum and copper; and nickel, chromium and copper reduce the amount of intermediate layer formed at the iron-aluminium interface. The rate of growth of the intermediate layer formed on Ni-Cr-Mo steel is very small.
(2) When aluminium coatings are made on alloy steel, the inner boundary of intermediate layer is flatter than that on carbon steel.
(3) The hardness of intermediate layer formed on alloy steels, except SEH3 and SUS7, is Hv 600-768. The hardness of those on SEH3 and SUS7 is Hv 370 and Hv 376 respectively.

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Grain refining effect on AZ 63 alloy of the various carbonaceous additives including lamp black, CaC₂, C₂Cl₆, C₆Cl₆ and vinylidene chloride was studied here. The metal was melted and treated with the above compounds under different temperatures and stilled for severol times, and then cast into shell molds for the test. From the test, it was found out that grain refining effects by each additive has different characteristics.
Grain refining effect of AZ63 alloy treated with C₂ Cl₆ was lost by remelting.
AZ63 alloys containing different amount of Be were treated with several ways, including fluxing, chlorination, super-heating, C₂Cl₆ addition, CaC₂ addition and then cast into green sand mold for making tension specimen with which tension and grain size were examined under T₄ condition.
Through the examination, the following formula was obtained: σ_B(kg/mm₂)=3.6N(grains/mm₂^1/4)+16.2

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