Several pieces of pure aluminium sheet ingots were trially produced from identically charged molten metal by semi continuous casting process. Under the different casting conditions, particularly the height of molten metal in the mold, and casting speed, the comparative examination was made on the components and structure of thus produced sheet ingots.
The findings were as follows:
The height of molten metal in the mold is a very important factor for getting good ingot. By lowering the height of molten metal, the segregation of ingot surface can be reduced and the structure gets uniform. The effect of casting speed is much less than that of the height of metal in the mold.

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This is to report on the experiments made for clarifying the influence of preheating temperature on recrystali ation of slab of high purity aluminium and several aluminium alloys.
In the case of high purity aluminium sheets (85% cold-rolled), the higher the pre-heating temperature, the higher the recrystallization one. The specimens pre-heated at 400°-450°C is softened most rapidly and shows bigger recrystallized grain size.
It is considered that the above-mentioned phenomenon are concerned with the change in the solubility of impurities contained.

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The components of the surface faults of hot-rolled stocks were examined by means of spectrum and X-ray analysis and the absorption spectrum of ultra-violet or infra-red rays. Through those experiments as above, it was found out that the components of the surface faults are Ca, Mg, Si, C and H, but it could not be determined how these elements constitutes the faults.

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On the cold rolled 3S sheet, which is one of non heat-treatable aluminium alloys, the manufacturing conditions after hot rolling process of slab, i. e. the direction of cold rolling, the cold reduction and the annealing temperature, are pursued on effect to the directionality of sheet. The results are summarized as follows:
(1) In this experiment, the ear by deep drawing of 3S sheet is small, and it seems that there is few troube in prouction.
(2) One-way (unidirectional) cold rolled sheet superiors the factor of the growth of ear in 45°-direction and grows small ear compare with cross way cold rolled sheet, and the former is in favour of production.
(3) The ear factor of 90°-direction grows strong with rising cold reduction.
(4) There is no remarkable difference in the directionality and the ear in the range of experimented annealing temperature (350-500°C).
(5) The closed connection between the directionality by means of Knoop ratio and the ear is confirmed as like the case of 2S, and the coefficient of correlation is 0.66.

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Continuing the previous report on 3S, the cold rolled 52S sheet, the manufacturing conditions after hot rolling process of slab, i. e. the direction of cold rolling, the cold reduction and the annealing temperature, are pursued on effect to the directionality of sheet. The results are summaeized as follows:
(1) In this experiment, the ear by deep drawing of 52S sheet is 0°-or 90°-ear in all.
(2) The ear is less than 2% notwithstanding annealing temperature, and this extent of ear is out of question for the using die in production process.
(3) There is not so distinguish difference between the one-way-cold (unidirectional) rolled sheet and the cross way rolled one.
(4) It is not consistent to the previous results that the directionality by means of Knoop ratio is in closed connection with the ear in deep drawing.

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In 1949, KOBE STEEL WORKS-LTD. started the study on titanium in co-operation with Dr. Nishimura and Dr. Kushima of Kyoto University and Dr. Asada of Osaka University. This study was industrialized in 1959 at Takasago Plant of the same company. The annual capacity of titanium ingot production then was 360 tons. Since then, improvement and modernization of technology and equipments have been carried out and at present, the production capacity of this plant is more than 600 tons.
The statistics shows that during the past two years, about 80 per cents of total consumption of titanium sponge was made by KOBE STEEL who melted it into ingot. In the United States, the aircraft and missile industries consumes 95 per cents or more of the total production of titanium mill products. In this country, however, the most of the titanium production goes to chemical industries, such as petrochemical, petroleum refining, synthetic fibre, urea, paper and pulp, sodium and other industries. In this connection, the most of the titanium products of the KOBE STEEL is what so called commercially pure titanium, in which "KS-50" is the most popular.
This report is to explain the properties of "KS-50."
By statistical means, it was clarified the quality standard of the metal forgings and that this standard is satisfactorily useful for manufacturing KS-50 titanium sheet, which has the metallurgical uniformity.
The analysis of varience for regression of yield strengh, tensile ductilities and oxygen contents upon tensile strength was made, and we obtained the conclusive evidence at 0.01 probablity level that the regression factor can be distinguished from residual errors
But, no relation was observed between tensile strength and iron contents of commercially pure "KS-50" titanium forgings.
Data obtained from the above-mentioned experiment are as follows:
Average of tensile strength: 39.6kg/mm²
Its standard deviation: 1.56kg/mm²
Average of elongation: 34.9%
Its standard deviation: 4.5%
Co-relation co-efficient between them: -0.43%
The equation of regression line for yield (y) to tensile strength (x): y = 0.97x-8.1
For elongation (y) to tensile strength (x): y = 84.9-1.26x
For oxygen contents (y) to tensile strength (x): y = 30.5x-490
From the calculation for the 95 per cent confidence intervals of population average in tensile properties and chemical compositions for the "KS-50" forgings, the following data were obtained:
For tensile strength: 39.4kg/mm²<μ<39.9kg/mm²
For yield strength: 30.1kg/mm²<μ<30.7kg/mm²
For elongation: 34.2%<μ<35.6%
For oxygen contents: 0.069%<μ<0.075%

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