Extrusion deformation of aluminum matrix composites reinforced by in-situ Ti@(TiAl3, Al) particles with a core-shell structure

Abstract

An aluminum matrix composite reinforced by in-situ Ti@(TiAl3, Al) particles with a core-shell structure was fabricated via ball milling and hot-pressing sintering. In order to modify the mechanical properties of the composites, two deformation modes were investigated: cycling extrusion-compression (CEC) and elliptical cross-section spiral equal-channel extrusion (ECSEE). The experiments demonstrated that both CEC and ECSEE are effective methods for refining the coarse grains that are formed during hot-pressing sintering. The strengthening mechanisms of load transfer and heterodeformation are of particular significance in the context of reinforced particles with a core-shell structure. ECSEE integrates torsion shear, extrusion, and upsetting deformation into a single. The shell of the Ti@(TiAl3, Al) particle is not destroyed in ECSEE because the predominant deformation modes are torsion and shearing along the axial direction. Therefore, ECSEE is an appropriate process for modifying the mechanical properties of aluminum matrix composites reinforced by Ti@(TiAl3, Al) particles with a core-shell structure.

Keywords: aluminum matrix composites, core-shell structure, extrusion deformation, property modification