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The hydrogen-induced plastic loss behavior of titanium alloys is often reported, but there are relatively few studies on high-strength aluminum alloys. In this article, the hydrogen-induced plastic damage behavior of 7085-T7651 high-strength aluminum alloy was investigated using a tensile specimen with pre-charging hydrogen, and the microstructure was characterized by transmission electron microscopy, scanning electron microscopy and time-of-flight secondary ion mass spectrometry. The results showed that 7085-T7651 high-strength aluminum alloy material has certain hydrogen embrittlement sensitivities, and with the increase of hydrogen-charging time, the hydrogen content and sensitivity of the material increases significantly. For the first time, the theoretical analysis and intuitive quantitative characterization of the hydrogen-induced plastic loss behavior mechanism on 7085-T7651 high-strength aluminum alloy is stated as the formation of Mg and H segregation formed at the crystal boundary, which will result in the weakening of the crystal boundary.

High-strength aluminum alloys are exposed to more and more environmentally-induced cracking failure behaviors during service. However, due to the hard to detect nature of hydrogen, and the special working conditions, failure research has obvious hysteresis and complexity, and it is impossible to truly reflect the material failure phenomenon and mechanism. In this paper, 7085 high-strength aluminum alloy is selected as the research material to simulate and reproduce the environmental failure phenomenon of aircraft under extreme working conditions (temperature 70 °C, humidity 85%). The results proved that high-strength aluminum alloy has environmental cracking failure behavior under extreme working conditions. The failure mode that was determined was due to environment-induced hydrogen and hydrogen-induced cracking, which is the result of the combined action of hydrogen and stress. Meanwhile, we demonstrate that high-strength aluminum alloy’s environmental failure behavior in an environment of high temperature and high humidity is different from traditional stress corrosion cracking behavior.

The internal friction (IF) behaviors of a series of LaCe-, Zr-, and La-based bulk metallic glasses (BMGs) were studied by a computer-controlled, conventional inverted torsion pendulum. The results indicate that with an increasing temperature, the IF also increases gradually in the supercooled liquid region, followed by a decrease caused by crystallization. BMGs with a good glass forming ability (GFA) usually possess a high IF peak value for an alloy system with the same constituent elements. Furthermore, the magnitude of the IF value (Qi−1) of the inflection point is an efficient criterion of GFA. The Qi−1 value is a valid criterion under the conditions of identical constituent elements and different element contents. However, Qi−1 and GFA have no relationship among different alloy systems.