The effect of alloying on the mechanical performance and substructure of aluminum at large strains

The Al-5Mg alloy, and the differential purity aluminium Al99.992 and Al99.5 samples were deformed in the range of true strains from 0.2 to about 80. The course of hardening of materials was found to be different. The proof stress of Al99.992 and Al99.5 saturates above the true strain of about four and eight, respectively. In Al-5Mg alloys, proof stress increases in the whole investigated range of deformations, showing however stepwise course with two ‘plateaus’ of the proof stress stabilization. The observations of microstructure show presence of microbands in all materials. In Al99.992 and Al99.5 microbands assume the form of thin elongated, free of dislocations subgrains. In Al-5Mg alloy microbands look like thin layers of high, local dense dislocations.