Development of materials and processing regimes for the enhancement of specific strength is a challenge for the aviation, aerospace and transportation industries. The paper analyzes the evolution of microstructural parameters and mechanical properties of the Al – 5 %Zr – 4 %Mn – 2 %Cu alloy obtained by mechanical alloying with subsequent hot pressing at temperatures between 350 and 450°C. High-energy ball milling for 10 h formed nanostructured granules of aluminum-based solid solution with the grain size of 20–30 nm and microhardness of ~460 HV. After hot pressing and further annealing, grains increased up to ~90 nm, the Al3Zr, Al6Mn and Al20Cu2Mn3 phases precipitated and the formation of zones free from secretions along the boundaries of the granules. The microhardness of granules after annealing to the compaction temperature decreased to ~300–340 HV, and the hardness of hot-pressed specimens did not exceed 280 HV, which was attributed to residual porosity. The lowest porosity (0.5 %) was found in specimens consolidated at 450°C, the compressive yield stress of which reached ~700 MPa at room temperature and ~170 MPa at 350°C.
Yakovtseva et al. (Wed,) studied this question.