On analysis of the pole figure, indicating the crystal orientation of rolled sheet of polycrystalline cubic metals, a three-dimentional distribution function is usually determined by expanding to Legendre's spherical harmonic function. This method is strict, but requires a considerablly difficult work.
In the present work, pole figures of many single or mixed typical textures corresponding to Gaussian distribution functions were obtained, and how the aspect of the pole figure varies with their deviation was shown. Thus, it may be useful to determine directly the correct preferred crystal orientation by comparing the measured pole figure with those of the typical texture patterns.

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The solubility in the α-phase of the Al-Cu-Sn alloy was studied by means of electrical resistivity and lattice spacing measurements. From the isothermal sections of the phase diagram at 520, 500, 480 and 460°C, it was found that the addition of Sn to the Al-Cu alloy had little effect on the solubility of Cu in the α-phase. This observation led to conclude that the aging suppression in the Al-Cu-Sn alloy was not explained by the significant decrease of Cu contents in the α solid solution.

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In order to study the influence of Mg content and holding temperature on the oxidation of molten Al-Mg (2-12%) alloys in air, oxides and their formation processes were examined by means of thermal gravimetry, X-ray diffractmetry and electron probe micro analysis. The results obtained are as follows:
The amount of oxides produced was in proportional to Mg content of the alloy, and different oxides were formed for the different holding time and temperature. On oxidation of the molten alloy, at first, Mg was selectively oxidized. And then, oxygen reacted at the interface between MgO and molten Al to produce an amorphous oxide containing Mg and Al. The amorphous oxide was crystallized to spinel type MgAl₂O₄ as the holding time elapsed. Owing to the difference of the reaction rate between following two reactions: Mg+1/2O₂→MgO and MgO+2Al+3/2O₂→MgAl₂O₄, at a temperature below about 775°C, the oxidation observed by the weight gain proceeded in two steps, and in one step at a higher temperature.

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Tensile fractured surface of annealed 5083 aluminum alloy sheet was examined by electron microfractography and electron beam scanning image analysis in order to study the relationship between the inclusions and tensile fracture characteristics at room temperature.
According to the electron beam scanning image analysis, Mn and Fe were usually segregated in the exact same location of the tensile fractured surface. Occasionally, segregation of Cr and Si was observed in the above location. Remarkable segregation of Si and Mg was also confirmed in the different location of the tensile fractured surface.
The former segregation was considered to be due to an intermetallic compound, such as Al₆Fe Mn, consisting mainly of Fe, Mn and Al, while the latter segregation was considered to be due to another kind of intermetallic compound, such as Mg₂Si, consisting primarily of Mg and Si.
The Al-Fe-Mn intermetallic compound was usually large in size ranging from about 5 to 10 microns and existed preferentially in large dimples, especially in the inner wall or bottom portion of the dimples. The Mg-Si intermetallic compound was usually smaller in size ranging from about 1 to 2 microns estimated by the electron scanning image and existed preferentially in the neighborhood of the opening portion of the dimples. Thus, such an intermetallic compound consisting primarily of Fe, Mn and Al was considered to be directly and most closely related to formation of large size dimples, indicating that voids or microcracks were initiated primarily at these inclusion particles either by decohesion from the matrix or by cleavage of the particles.
Besides Al-Fe-Mn and Mg-Si intermetallic compounds, existence of an Al-Mg intermetallic compound was also observed in the tensile fractured surface of the annealed 5083 aluminum alloy sheet.

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The chip flow angle in dry drilling of aluminum alloys is larger than the inclination angle of cutting edge, and this is not in agreement with stabler's rule. In present study, the relation between the chip flow angle and surface roughness was investigated from the standpoint of the profile of the built-up edge. A quick-stop apparatus was used in this experiment to "freeze" the cutting action of cutting edge. The results obtained were as follows.
1) The chip flow angle is not affected by cutting speed, but it decreases with increasing helix angle and increases slightly with increasing feed. The chip flow angle is affected by the material, cutting fluid and drilling depth.
2) The equivalent inclination angle formed by the built-up edge at the outer corner of cutting edge approaches to the chip flow angle.
3) The surface roughness seems generally to increase with the increase of the equivalent inclination angle and then the increase of the chip flow angle.

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