Metastable theta'-Al2Cu precipitates enhance mechanical properties of Al alloy, but gradually transform to theta phase due to diffusion related coarsening at higher temperatures ( > 200 degrees C). To improve understanding of the phase instability and transformation of theta'-Al2Cu, we investigated ...
These observations imply that the strain fields of the interface dislocations as well as the coherency strain fields at the theta'-Al_2 Cu/matrix interface plays an important role in the process of heterogeneous precipitation of the Al_3Sc phase on the theta'-Al_2Cu phase. The Al_3Sc ...
The theta'-Al2Cu phase in an Al-4Zn-2Cu-1Mg-0.7Si (wt.%) alloy was investigated by means of scanning transmission electron microscopy. With our specific alloy composition, the phase is often formed with stacking faults on {101}(theta') and {001}(theta') planes. The stacking faults on...
An Al-2.5 mass percent Cu-0.23 mass percent Sc alloy is strengthened by fine and uniform distribution of coherent spherical L1_2-Al_3Sc phase and semicoherent plate-like #theta#'-Al_2Cu phase, which precipitate during aging. These precipitates interact on growth and heterogeneous precipitation ...
The theta (Al_2Cu), S (Al_2CuMg), and T_1 (Al_2CuLi) intermetallic constituents and precipitates found in age-hardenable aluminum alloys play important roles in the localized corrosion behavior of Al-Cu-(Mg, Li) alloys. Most of the common understanding of the behavior of these phas...
Grain boundaries in metals would introduce extra nucleation energy to promote the growth of theta' precipitate during ageing process. The influence of grain boundaries on the distribution behavior of two theta' precipitates variants (010) and (001) were studied in Al-2Cu alloys bicrystals. Ageing ...
To study localized corrosion mechanism of 2 x x x-series Al alloys containing theta' and S precipitates, the electrochemical behaviors of a three-electrode coupling system of alpha(Al) substituting for alloy base, simulated bulk theta' and S in 4.0% NaCl solution at pH 6.1 have been ...