Wear characteristics of 5083 aluminum alloy sheet, rubbed with the same alloy, 4-6 brass and S45C carbon steel were discussed mainly in view of the wear loss of the rubbed specimens.
From the wear loss versus sliding distance curves for the 5083 aluminum alloy specimen rubbed with the same aluminum alloy, two typical and distinct ranges, that is, the initial wear range and the steady wear range, were confirmed. It was also observed that the steady wear range was reached after the initial wear range of about 100m of sliding distance which accompanied a drastic variation of frictional force under the following sliding conditions; applied load of from 7 to 17kg and sliding speed from 0.11m/sec to 0.55m/sec. A trace of localized melting of contact asperities of the 5083 aluminum alloy surface was suggested from the scanning electron microscope observations of the worn surface.
The wear loss of the 5083 aluminum alloy rubbed with 4-6 brass was negligibly small under the above experimental conditions, while the wear loss of the 4-6 brass specimen was remarkably large probably due to a typical lapping effect of the 5083 aluminum alloy specimen inlayed with particles or patches of the worn 4-6 brass.
The wear loss of the 5083 aluminum alloy specimen, rubbed with S45C carbon steel, was influenced generally little by the sliding conditions. While, the wear loss of S45C carbon steel was markedly effected by the sliding speed and decreased remarkably with its increase. This was probably due to an increase in local melting of the contact asperities of the 5083 aluminum alloy specimen. By the X-ray diffraction analysis of the wear debris produced by the aluminum alloy and S45C carbon steel rubbed with each other at a sliding speed of 0.11m/sec and under an applied load of 7 to 17kg, strong diffraction lines of metallic aluminum and weak single diffraction line of iron oxide (FeO) were confirmed.
The temperature rise of the contact surface of the 5083 aluminum alloy rubbed with the same aluminum alloy was discussed in view of both experimental and theoretical considerations. Measured values of the temperature near the contacting surfaces were from 33 to 96°C for a sliding speed of 0.33m/sec and under an applied load of 7 to 17kg, while theoretical values were about 35 to 125°C.

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When pure aluminum is immersed in hot water, hydrated oxide films are formed. The effect of these films on the adhesion of polyethylene to aluminum surfaces was investigated. The results obtained are as follows:
(1) As the treating temperature rose, the growth rate of the hydrated oxide film increased gradually and the amount of weight gain reached a constant value in shorter immersion time. Also the weight gain of hydrated oxide films varied depending upon the type of treating solutions; smallest in underground water, medium in deionized water and largest in a solution of triethanolamine in deionized water.
(2) The constituent change of hydrated oxide films during the hydration treatment was examined by the OH bending band of reflection infrared spectra. At the initial period of growth of films, the absorption spectrum of OH bending band was observed at nearby 1070cm^-1, but was shifted to nearby 1090cm^-1 as the treatment proceeded, suggesting that the change of the hydration state occurred to hydrated oxide films.
(3) For a high treating temperature and a long treating time, high peeling strength was obtained for the adhesion of polyethylene to the hydrated oxide film on aluminum. When treated in the solution of triethanolamine in deionized water, the peeling strength increased remarkably. But when treated in underground water, its increase was rather small.
(4) In the initial period of hydration, the peeling strength temporarily decreased. This was inferred that at this stage hydrated oxide films showed week cohesion and cohesive failure occurred at these films. This conclusion was justified by the characteristic X-ray images of Al Kα observed for hydrated aluminum oxide films attached to polyethylene surfaces after peeling off.

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Growth-twinned polycrystalline aluminum of which crystallographic orientation was three-dimensionally controlled was cold-rolled in the directions {111} <112>, {111} <110>, {001} <100> and {001} <110>. Analyses of pole figures and slip lines lead to understanding of the formation of the rolling textures and the factors contributing to it, such as grain boundaries, neighboring grains and twin planes.
Symmetrical geometry of the active slip systems about a plane containing ND-RD is an important factor to govern the formation of rolling textures of a pure metal type. Finally stable orientations are {110} <112>, {112} <111> and n {123} <121>.
If the active slipping direction lies symmetrically on the ND-RD plane, deformation bands are formed when the slip systems are unstably active due to oscillation of the stress and when the slip systems lie unsymmetrically on the ND-RD plane resulting in increase in 1/μ of the slip systems.
Grain boundaries, twin planes and neighboring grains often cause independent actions of the slip systems having the maximum resolved shear stress in polycrystalline aluminum. The slip rotation in a single crystal is hardly applicable to each grain of polycrystalline aluminum.

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