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Al2NbTi3V2Zr alloys were prepared by low‐energy (LE) and high‐energy (HE) ball milling and subsequent vacuum hot pressing. The corrosion behavior of the Al2NbTi3V2Zr alloy in 10 wt% HNO3 solution was investigated. Results showed that the HE bulk exhibited improved corrosion resistance than the LE bulk. Both had lower corrosion rates than Ti64. The LE bulk displayed localized corrosion whereas the HE bulk exhibited general corrosion and a wide passive region. The corrosion resistance of the alloy depended on the content of the secondary phase for the LE bulk, whereas grain size of the secondary phase and matrix influenced the HE bulk.

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Abstract

The creep behavior and microstructural evolution of three Al–Cu–Mg–Ag alloys with Cu content around its solid solubility limit in Al (5.65 wt %) were investigated at 180–240 °C and applied stress of 150–300 MPa. The creep resistance of aged alloy, which is mainly determined by the number density of Ω phase, is the best for 6.00 wt % Cu, better for 5.30 wt % Cu, and the worst for 5.65 wt % Cu. After solid-solution treatment, the lowest Cu content in the Al matrix for the alloy with 5.65 wt % Cu is observed due to the existence of more residual phases. It results in the lowest number density of Ω phase the following aging and poor creep resistance. Increasing temperature from 180 to 240 °C at the same stress (225 MPa), the steady creep rate of alloys increases by 225 times, which is apparently larger than that (26 times) for increasing stress from 225 to 300 MPa at the same temperature (180 °C). It indicates that the coarsening of the Ω phase with increasing temperature should be more serious than that with increasing stress. The creep mechanism of Al–Cu–Mg–Ag alloy can be attributed to the dislocation climb with the existence of threshold stress.