Abstrakt
The paper reports results of a study aimed at understanding the precipitation processes of quaternary coldrolled AlMnScZr alloys during isothermal annealing at 300 oC and 400 oC and during annealing with constant heating rate from room temperature up to 570 oC. Th e resistivity, conductivity and microhardness behaviour was compared to microstructure development.
The changes in resistivity and conductivity of the alloys at temperature above ~ 360 oC are mainly caused by precipitation of the Al6Mn particles. This precipitation is dependent on deformation degree.
The deformation of the alloys shifts the Al6Mn-phase precipitation to lower temperatures compared to the mould-cast AlMnScZr alloy. The activation energy for Al3Sc- and Al6Mn phase precipitation was also determined.
The obtained results agree with conclusions on the cold-deformed AlMnScZr alloys studied in our previous works.