Improving Mechanical Properties of Chips-Based Aluminum Extrudates by Composite Hot Extrusion

A new composite severe plastic deformation die was designed that integrates shearing and extrusion, resulting in a method termed as variable channel angular extrusion (VCAE). In the present study, conventional extrusion and VCAE were employed to recycle 6061 aluminum alloy chips. The improvement of mechanical properties is attributed to the refinement of intermetallic compounds (IMCs) and grain size of the aluminum matrix, the good combination of chip interface and the hindrance of dislocation movement by nano-IMCs and oxides. Tensile testing demonstrated the exceptional properties of VCAE-T6 alloy at room temperature, with an ultimate tensile strength of 362 MPa, a yield strength of 268 MPa.