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• Fine uniformly dispersed broken precipitates were obtained by ECAP. • The dislocation and broken precipitated phase enhanced the uniform corrosion. • The corrosion rate of AA8176 was reduced at 0 °C with ECAP technology. Electrochemical tests and immersion experiments were employed to investigate the corrosion behaviors of the Al-Fe alloy (AA8176) processed by equal channel angular pressing (ECAP) in 3.5 wt% NaCl solution at different temperature (25 °C and 0 °C). It was worked out that after ECAP, with the reduction of grain size, the fragmentation and uniform distribution of precipitated phases increased the number of pitting corrosion but reduced its size, the increase of grain boundary density and the reduction of precipitated phase aggregation decreased the degree of intergranular corrosion. AA8176 changed from local corrosion to uniform corrosion, which provides a new idea to improve the corrosion resistance of Al-Fe alloys. [ABSTRACT FROM AUTHOR]

The precipitate evolution, strength and corrosion resistance of an Al–Zn–Mg–Cu alloy processed by cryorolling, warm rolling and final aging have been investigated. A large number of spherical Zn-rich GP zones formed after warm rolling. In-situ transmission electron microscopy (TEM) observation indicated that the GP zones are stable during aging treatment and can serve as nuclei for subsequent precipitates, leading to homogeneous distribution of precipitates in the matrix after aging. TEM results also showed that ultrafine subgrains were developed in the deformed microstructure during aging. The high density of precipitates and dislocations combined with grain refinement contribute to the higher strength of the thermo-mechanically treated alloy compared with the peak-aged alloy. On the other hand, the η phase with C15 cubic structure having ‧‧‧RR‧‧‧ stacking is found in the thermo-mechanically treated alloy and is different from one with C14 hexagonal structure having ‧‧‧RR−1‧‧‧ stacking that is commonly observed in conventionally aged alloys, where R and R−1 represent rhombic layer and the relatively 180°-rotated rhombic layer, respectively. The transition from ill-defined stacking to C15 stacking and further to C14 stacking is observed in the structure of a η phase. Besides, the combination of warm rolling and aging can avoid the formation of continuous grain boundary precipitates, which is beneficial to the corrosion resistance of the alloy. [ABSTRACT FROM AUTHOR]

In this work, a nanocrystalline (NC) Cu-10at.%Ta alloy is irradiated with helium at different temperatures to assess the stability and effectiveness of Ta nanoclusters in trapping helium and suppressing swelling. Advanced microstructural characterization of the room-temperature irradiated specimens indicated the presence of small He-bubbles (∼1-2 nm) at the peak damage depth mainly at the core and along the interface of Ta nanoclusters with Cu matrix. Few bubbles were found along grain boundaries, with much smaller bubbles homogenously distributed within the copper lattice. High-temperature irradiation exhibited bubbles of ∼3-5 nm, which were primarily associated with nanoclusters as compared to other locations, with no observed faceting of the bubbles. Atom probe analysis confirmed helium partitioning to the Ta nanoclusters indicating the effective entrapment of these He atoms. [Display omitted] [ABSTRACT FROM AUTHOR]