The lattice structure of aluminium has been studied by means of measuring the Bragg angle of X-ray diffraction on super-purity aluminium . The lattice is distorted in the annealed state as well as in the cold forged state. The degree of relative distortion is calculated on some orbitrary standard plane

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The surface cracking of ingot is happened by the influence from the chemical compositions.
This report is on the study of hot cracking of alloys ingots cast by ring casting method. Al-Fe-Si cast alloys and Al-Mg-Si alloys are used for this experiment where Ti or Cu is added to these alloys and composition-cacking graphs are prepared for each system of the alloys. With these graphs, the effects of Ti are examined by comparison. When 0.04-0.15% Ti is added, the effect is well recogniged at 0.04% Ti. Effect of Cu to Al-Mg-Si system is examined with various quantities of Cu. It was found out from the examination, the cracking increased when 0.3% Cu is added, but if 2% Cu is added it is rather decreased.

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The earing phenomenon in the deep drawing test was mentioned in previous report. In this test 1 blanks which were cold-worked in one way by 73.4%, 87.1 and 92.9% respectively were used. These were made of contenuous casting 2S slab. The slab was rolled after reheated differently long (2-7 hours) and then annealed for one hour under the temperature in the range of 265-400°C. After that, the directionality of the blank was detected through the Knoop indenter.
In this paper, the directionality is detected by means of the decrement of Harbert pendulum with the similar blanks, the charactoristics of which have been known through the above-mentioned tests. The relations between both detections is discussed and the possibility of the application of the Harbert pendlum in industrial fields is studied. The results of the study are summarized as follows:
(1) The directionality detected by the decrement the logarithmic decrement) of the Harbert pendlum agrees with the charactoristics mentioned in the previous report and this fact proves that this way of detection is reliable
(2) The decrement is closely connected with the earing in deep drawing and the earing appears in prodominant direction where the decrement is smallest.
(3) If the ratio p (the difference between the minimum decrement and the mean decrement of Harbert pendulum the/mean decrement of Harbert pendulum) is chosen in the minimum decrement direction, the correlation between the ratio p and the earing e is related with 0.66 of the correlative coeffcienty.
(4) The forecast of the earing by the directionality detected by the Harbert pendulum is slightly inferior to the detection by the Knoop indentor in its accuracy, but the Harbert pendulum may be used industrially for forecasting the earing without the deep drawing in practice.

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The effect of the added element to aluminium, especially Mn and Sn, on the directionality of sheet is purseud by detecting the directionality by means of the Knoop indentor. The findings summed up as follows:
(1) It is possible that the directionality is controled by adding Mn, but the directionality changes very sensitively in accordance with the amout of the added elements and the annealing temperature, and on the other hand elongation decreases largely as the added Mn increases. So Mn is not suitable as the added element.
The recristallization temperature raises considerably by aadding Mn. This fact agrees with the former reports.
(2) The directionality can be controled by increasing Sn content, and in this case the directionality does not much fluctuate slightly and is stabilized notwithstanding the change in annealing temperature. The elongation decreases a little by adding Sn. So, 0.5-2.0% Sn adding is effective for the control of directionality.
It seems that the recristallization temperature raises considerably by adding Sn.

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Following to the first report, the effect of Fe, Mg, and Ti added elements to aluminium on the control of directionality of sheet is studied. The results are as follows:
(1) By adding Fe, the directionality can not be controled, and the recrystallization temperature of aluminium sheet is slightly lowered this fact thus agrees with the finding mentioned in the previous reports.
(2) When Mg is added in aluminium within the range of 1.0-3.5%, the directionality can be softened or eliminated and is insensible and stable considerably in spite of the change in the annealing temperature, therefore Mg is an effective element for controling the directionality. The hardness increases when it is added and even after softening the hardness does not decrese much.
It semms that the recrystallization temperature gets slightly down.
(3) It is possible that the directionality eliminated by adding Ti, but this temperature range is narrow, so Ti is not so effective element.
The recrystallization temperature goes to upward by adding it.

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Substructures were formed within the grains of polycrystallines aluminium and aluminium-manganese alloy by prestrain-annealing treatment, and the hardening due to the presence of substructures was investigated. Results are as follows:
(1) In both cases, remarkable hardening was observed when annealed at the suitable temperature after the prestrain is given.
(2) In general, the rate of hardening proportionally increases with the prestrain. But when highly heated, it does not proportionate to the prestrain, but decreases after it passed the maximum value. This tendency is particularily remarkable in 99.8% aluminium.
(3) Work-hardenability of the stress-strain curve is constant irrespective of the value of the prestrain.
(4) The rate of hardening by the effect of the substructure hardening is maximum in 99.8% aluminium and decreases by the addition of manganese.

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A study was made on the effects of extrusion conditions, heat-treating temperature and chromium content on the tensile strength of the extruded 61S. A extrusion effect was observed when billets were extruded at the temperature higher than 400°C, and then the tensile strength increased with the elevation of the billet temperature. The critical tempertaure of the billet which produces the extrusion effect is a function of chromium content, and the temperature becomes lower according with the increase in chromium content. The critical chromium content which srises the extrusion effect is about 0.3 percent, and the tensile strength is nearly constant regardless of the billet temperature when chromium is less than the critivcal content. The extrusion effect was observed markedly when the billets were extruded without soaking. Both the solution heat-treating temperature and the extrusion ratio affect on the extrusion effect. It is obvious that the above mentioned extraordinary strengthening characteristic is connected with some factors governing the recrystallization temperature of extruded 61S.
We discussed the above results and suggested that the extrusion effect may be resulted from the overlap of two effect i. e. substructure hardening effect and the strengthening effect resulted from the interaction between the edge dislocations at subboundaries and the solute atoms in G. P. zones formed at subboundaries in low temperature aging, and that a press effect can be explained rather by the above mentioned mechanism than the strengthening effects depended on texture and anisotropoic hardening.

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This is the report of a study on photometric method by use of α-nitroso-β-naphthol or β-nitroso-α-naphthol, for determining trace Co in aluminium. Under this method, citric acid is added to NaOH solution of aluminium and the following treatment are made:
(1) α-nitroso-β-naphthol
The solution is adjusted to pH 5 by use of HCl and α-β reagent is added to it. Boiled about 5 minutes, the solution is cooled to room temperature. Benzen is added to the solution and shaken for 2 minutes. Benzene layer is washed with dilute HCl and NaOH solution, and then measured the absorbancy at 410mμ.
This method can only be adapted to the trace Co (0.02ppm and over) in pure aluminium.
(2) β-nitroso-α-naphthol
The solution is adjusted to pH 8. β-α reagent and benzene are added to it. The extructed benzene layer is washed out in similer way as above and the absorbancy is measured at 365mμ.
This method can be adapted to determination of trace Co (0.05ppm and over) in aluminium and its alloys.

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