Polarization measurements were employed to study the corrosion behavior of aluminum in 5 mass% H₃PO₄ solutions at different solution temperatures. The electrochemical parameters and corrosion rates were calculated by using the differential polarization method (DPM). It has been shown that the reduction reaction of hydrogen ions is H++e−→H_ad and its corrosion rates at the solution temperature of 298 K, 303 K and 313 K are 0.040, 0.28 and 0.30 mA cm−², respectively. Corrosion rates estimated by DPM are roughly correspond to the values which obtained from corrosion mass loss at various temperatures (298 K, 303 K and 313 K).

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A {001} ⟨100⟩ oriented aluminum single crystal was deformed by nine cycles of accumulative roll bonding which corresponded to a total equivalent strain of ε=7.2. The formation of {4 4 11}⟨11 11 8⟩ component in deformation texture was examined by using electron back-scatter diffraction method. The specimen processed by five cycles ARB (ε=4) developed four variants of {123}⟨634⟩ orientation in the deformation texture. Between the five and nine cycles, the four variants of {123}⟨634⟩ rotated toward {4 4 11}⟨11 11 8⟩ and {112}⟨111⟩ orientations. The specimen after the ninth cycle had a weak texture which was mainly composed of {4 4 11}⟨11 11 8⟩, {112}⟨111⟩ and {123}⟨634⟩ components. The results obtained in the present study indicate that {4 4 11}⟨11 11 8⟩ and {112}⟨111⟩ become the primary and secondary stable orientations in the specimens deformed by accumulative roll bonding to the extremely high strain. The occurrence of the cyclic ratcheting which was reported by Heason et al. was also investigated. The cyclic ratcheting, which causes the formation of {4 4 11}⟨11 11 8⟩ in the center layer, did not have much effect on the {001}⟨100⟩ oriented single crystal.

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