Compressive deformation study on bimodal AA 4032 alloy produced by ball milling

The microstructure, mechanical properties and deformation behavior of bimodal structured nanocrystalline AA 4032 alloy are investigated in the present work. The bimodal structure alloy powders are fabricated using blending of coarse grained powders with nanocrystalline powders. The nanocrystalline powders are prepared by mechanical alloying using high energy ball mill for 30 h. A different mass fractions of coarse grained powders (micron size powders or micro powders) are taken for blending and the powders are consolidated by hot pressing to produce bulk bimodal alloys. The addition of micron sized powders is improved the ductility of the bimodal alloy along small reduction strength when compared with nanocrystalline alloy. The deformation of the bimodal alloy is due to highly localized plastic deformation under uniaxial compression. The failure of the alloy is due to shear localization and cavitations.