Sheet ingots of 99.2%Al and several kinds of other Al alloys containing small amount of Ti were produced by semi-continuous method and by tilting book mould method. Micro-structure and macro-structure at various parts were observed and compared. The micro-structure was examined by means of polarized light after anodizing and the crystals of the different orientations were distinguished.
The following are the findings:
1. The finer macro-structure is obtained by adding Ti 0.04%. But this gives influence only to the macrostructure but not to the micro-structure.
2. Long dendrite crystals and large network of compound do not appear when Ti is added. It will be because of the fact that the growth of the crystals is prevented by Ti. It may also be said that the addition of Ti tends to uniform the micro-structure.
3. Feather crystals, which usually appear at the part of pouring gate of the semi-continuous cast ingot, do not appear, when Ti is added.
4. The relation between crystals through macro-structure and grains through micro-structure were comparatively explained, particularly by means of polarized light.

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The X-ray diffraction analysis and the microscopic examination have been made on the aluminium sheet which was previously used for the examination on the ear in deep drawing. This is the one which has been hotrolled under the initial temperature of 500°C after pre-heated for 5 hours at 500-520°C and cold reducted 87.1% down to 0.9mm.
The findings are as follows:
(1) From the x-ray examination, it has been found out that in case the rolling texture in remained even after annealed, the 45°-ear is particularly remarkable, while the ear is small when the rolling texture is not remained much.
(2) Through the microscopic examination, the same results have been obtained as through the X-ray analysis: The rolling texture is remarkably remained in the sheet which makes big 45° direction ear when deep-drawn, while in the case of the sheet which makes small ear, the structure is almost completely changed into the recrystallization structure.
(3) It has been also found that the earing phenomenon has some correlation with the directionality of sheet, which is obtained by the statistical means from the orientations of crystal grain found out through the etching pit.

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It was measured squeeze pressure by the strain gauze installed on the back of squeeze roll support arm.
It was found that as squeeze pressure rose, maximum welded strength increased, also it was found that with constant welding speed, squeeze pressure indicate variation in proportion to welding electric current.

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The strength of welded parts under different welding conditions-required electric currency for welding and welding speed-was measured. It was found out that under any welding speed, the minimum amound of required currency shows the maximum welding efficiency and that the required currency decreases as the welding speed increases. It was also found that the width and strength of welded part is almost in proportional relation.

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When Mg and Mn are added to 2S-Aluminium alloy, the electric conductivity of the metal is changed. And the critical amount of electric currency for welding varies in proportion to the electric conductivity of alloys.

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"Reflectal" alloy, which contains 2%Mg on the basis of 99.99% aluminium, is one of the best materials for the bright anodizing. But a large number of "white spot blooms" oftenly appear on the coloured anodized surface, when sealed in steam. When sealed in boiling deionized water, however, any white spot is not found.Such phenomenon has been studied here, and the following findings have been obtained:
1. Very small content of Na gives a big effect to the white spot blooms.
2. White spot blooms do not appear when the alloy contains Na less than 0.0005%.
3. White spot blooms seem to be caused by "free Na" formed by the dissociation of [Al Na Si] compound which takes place by the excessive Mg.

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Microscopic observation during creep tests was made on magnesium and its alloys; Magnox A12, Magnox C, ZA and ZW1.
The creep phenomena of these alloys were studied with the initial stress of 0.25kg/mm² at the temperature of 350, 400 and 450°C. These materials ruptured in the brittle or ductile state under creep tests. The cavities in the ruptured metals seemed to be influenced by the fracture state and could be observed chiefly in the materials which showed the brittle fracture.
Grain boundary sliding, grain boundary migration, slip in grain, formation of sub-boundary and fold formation have been observed during the creep test. The amount of grain boundary migration increased with elevating the test temperature. The grain boundary migration was hardly observed on the boundaries which were approximately parallel with the stress axis at any testing temperature.
The study on oxidation-resistant properties were also carried out on pure magnesium and its alloys mentioned above at the temperature of 450, 500 and 550°C. The oxidation-resistance of Magnox A12 and Magnox C containing beryllium were distinctly better than that of other alloys.

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By use of ARL 1.5m production control quantmeter, analysis of titanium and its alloys have been carried out through point-to-plane method.
The operation conditions are established as follows:
The results of analysis for Fe, Si (impurities); Ni, Cr, Mn (alloying elements) are successfully carried out on a routine analysis, and these elements are determinable with coefficient of variation of about 4-10%.

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