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In this paper, based on in situ synchrotron radiation SAXS technology, the effects of stress field, temperature field and thermo-mechanical coupling conditions on the evolution of residual stress are discussed, respectively. The results show that the continuous increase of the external load led to the increase of the residual stress perpendicular to the tensile direction of the 2A14 aluminum alloy, and when the external load closed to the yield strength, the change of the residual stress was no longer significant. Under the action of temperature, the residual stress of 2A14 aluminum alloy reduced after the process of heating–holding–cooling. Under the action of thermo-mechanical coupling, the recovery effect of aluminum alloy was triggered, the energy storage of deformation was released, the lattice strain was reduced and the residual stress introduced by external load was reduced. [ABSTRACT FROM AUTHOR]

In this paper, a portable residual stress tester and synchrotron radiation diffraction technique were used to measure the residual stress distribution of thick 2A14 aluminum alloy plates under different aging conditions after solution treatment. The stress changes after solution and aging were analyzed using metallographic structure observation, electron backscattered diffraction (EBSD), X-ray diffraction (XRD), and other characterization methods. The results show that after solution treatment at 500 °C and aging at 170 °C, the second phase precipitates, lattice distortion is released, and the stress level gradually decreases with aging time. The residual stress of the plate comprises compressive stress; there is stress concentration in the central area. The stress distribution obtained by the two residual stress calculation methods, cosα and sin2ψ, under different process conditions was consistent. [ABSTRACT FROM AUTHOR]

In this paper, the tribocorrosion behavior and synergistic effect of 7075-T6 aluminum alloy under different applied loads (100, 150, and 200 N) and sliding velocities (100, 150, and 200 rpm) were studied in a 3.5 wt.% NaCl solution. Tribocorrosion experiments were conducted in a tribobocorrosion system with pin-on-disc testing. The results show that the interaction between applied load and sliding velocity significantly affects the mechanical and electrochemical properties of 7075-T6 aluminum alloy. Increases in sliding velocity and applied load will accelerate the corrosion. Due to the synergistic effect of corrosion and wear, the wear rate is almost unchanged as the sliding velocity increases. When the applied load increased from 100 to 200 N, the wear rate increased from 1.97 × 10−5 to 2.08 × 10−5 mm3/N·m, and the delamination wear phenomenon was aggravated. [ABSTRACT FROM AUTHOR]

• A tribocorrosion mechanism of aluminum alloy in the deep ocean is first proposed. • The tribocorrosion mechanism relies on interaction of mechanics, chemistry and electrochemistry. • The tribocorrosion mechanism is different under different hydrostatic pressure. • The corrosion accelerates wear is the main failure factor of materials during rubbing. • The rise of hydrostatic pressure will inhibit the formation of OH−. To understand the tribocorrosion behavior and mechanism in the deep ocean, the wear behavior of 7075-T6 aluminum alloy in 3.5 wt. % NaCl solution under the hydrostatic pressure of 0.1 MPa-30 MPa was investigated. The wear and corrosion mechanism of the aluminum alloy under different hydrostatic pressure were discussed, and its tribocorroison model was presented. Results show that mechanics, chemistry and electrochemistry interact with each other and accelerate the tribocorrosion process under the effect of high hydrostatic pressure. And the corrosion accelerates wear is the main failure factor of the aluminum alloy under a high hydrostatic pressure. [ABSTRACT FROM AUTHOR]