Bulk Behavior of Ball Milled AA2124 Nanostructured Powders Reinforced with TiC

Abstract

In the current research work, a top-down approach was employed for the refinement of a micron scale AA2124 alloy powder 40 μm in average size using high-energy ball milling up to 60 hours. The produced nanopowders were investigated compared to the micron gas atomized powder both in the monolithic and the reinforced composite states. 1 μm powder of TiC with internal structure <100 nm was used for the reinforcement of the 2124-Al matrices. Milling time of 36 hours produced a <100 nm nanopowders with internal structure size <20 nm. The nanopowder monolithic consolidates exhibited compressive strength of 388 MPa compared to 313 MPa for micronpowder one. Addition of TiC nanostructured powder to the nanopowder consolidated matrix resulted in increase of 130% in compressive strength compared to that produced for the microscale one. Nanopowder of Alalloys produced by mechanical milling reinforced with 10 wt% TiC is recommended for products suitable for high wear and erosion resistance applications. Peak aging increased the hardness and compressive strength of the as compacted micronpowder matrices by an average of 188% and 123%, while increased that of the nanopowder matrices by an average of 110% and 117%, respectively.