Equal-channel angular pressing (ECAP) is known to induce significant grain refinement and formation of tangled dislocations within the grains. These are induced to evolve to form low-angle boundaries (i.e., cell boundaries) and eventually high-angle boundaries (i.e., grain boundaries). On the other hand, precipitation sequence of age hardening aluminum alloys can be significantly affected by pre-straining, and severe plastic deformation. Thus, ECAP is expected to influence the T6 response of aluminum alloys. In this study, a complex Al-Cu-Mg-Li-Ag-Zr-Sc alloy was subjected to ECAP following different straining paths. The alloy was ECAP at 460K via route A, C, and by forward-backward route A up to 4 passes. The alloy was also aged at 460K for different durations after ECAP. It resulted that T1-Al2CuLi phase was the one that mostly showed a precipitation sequence speed up induced by the tangled dislocations formed during ECAP. The T1 phase was found to grow with aging time according to Lifshitz-Slyozov-Wagner power-low regime.
Role of high-temperature Equal-Channel Angular Pressing strain path on secondary-phase precipitation in a T6-Al-Cu-Li-Mg-Ag-Zr-Sc alloy
Acierno S.;
2021-01-01
Abstract
Equal-channel angular pressing (ECAP) is known to induce significant grain refinement and formation of tangled dislocations within the grains. These are induced to evolve to form low-angle boundaries (i.e., cell boundaries) and eventually high-angle boundaries (i.e., grain boundaries). On the other hand, precipitation sequence of age hardening aluminum alloys can be significantly affected by pre-straining, and severe plastic deformation. Thus, ECAP is expected to influence the T6 response of aluminum alloys. In this study, a complex Al-Cu-Mg-Li-Ag-Zr-Sc alloy was subjected to ECAP following different straining paths. The alloy was ECAP at 460K via route A, C, and by forward-backward route A up to 4 passes. The alloy was also aged at 460K for different durations after ECAP. It resulted that T1-Al2CuLi phase was the one that mostly showed a precipitation sequence speed up induced by the tangled dislocations formed during ECAP. The T1 phase was found to grow with aging time according to Lifshitz-Slyozov-Wagner power-low regime.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
