Surface hardening of aluminum-magnesium alloy by introducing a small addition of copper powder during friction stir processing.

The paper shows the peculiarities of changes in the structure and properties in the composite material based on aluminum alloy 5056 during friction stir processing with the introduction of 1.5 vol.% pure copper powder. It has been revealed that with small additions of copper powder even starting from a small number of passes by the tool along the machining line a fairly uniform distribution of particles in the volume of the stir zone is achieved. The mechanical properties during machining with the 1st pass are reduced relative to the properties of the base metal. After the 3rd pass, the material properties are already at the level of the base metal properties. After the 4th pass, an increase in strength relative to the base metal is achieved. It is noteworthy that even after 4 passes along the machining line, small amounts of pure copper unreacted with the base metal remain in the structure of the stir zone. [ABSTRACT FROM AUTHOR]