Developing a strategy for the processing of age-hardenable alloys by ECAP at room temperature

It is well known that age-hardenable alloys are generally difficult to process by equal-channel angular pressing (ECAP) at room temperature because they invariably fail by catastrophic cracking or segmentation. Experiments were conducted on two supersaturated Al–Zn–Mg alloys with the objective of developing a strategy for the processing of age-hardenable alloys at room temperature. The results from these experiments demonstrate that successful pressing may be undertaken by conducting the pressing operation very quickly (typically within <10 min) following a water quench from the solution heat-treatment temperature. It is also shown that there is a significant increase in strength in the alloys even when the ECAP is performed through only a single pass. This latter result has important implications for industrial processing.