Hot deformation behavior of the AA6016 matrix composite reinforced with in situ ZrB₂ and Al₂O₃ nanoparticles

Abstract

The hot deformation tests of in situ ZrB 2 and Al 2 O 3 nanoparticles reinforced AA6016 matrix composite were studied at deformation temperature of 300°C-450°C and strain rate of 0.001-1 s −1 . In this paper, the ZrB 2 and Al 2 O 3 nanoparticles were successfully prepared by direct melt reaction method firstly. Based on experimental results, the flow stress increased rapidly with the increasing true strain and decreased with the increasing temperature. Constitutive equation of the composite can be established based on the Arrhenius constitutive model. The processing map based on dynamic material model showed two stable processable domains: Domain A(300-360°C/0.08-0.01 s −1 ), which was controlled by dynamic recovery and domain B(410-430°C/0.37-1 s −1 ), which was typical dynamic recrystallization structure. The microstructural changes of the samples after deformed were observed through optical microscope (OM), scanning electron microscope (SEM) and transmission electron microscope (TEM). It was concluded that these two kinds of reinforced particles can greatly promote recrystallization nucleation at high temperatures. Thus, domain B is optimum hot processing window.

Investigating the Post-Sintering Thermal and Mechanical Treatments on the Properties of Alumina Reinforced Aluminum Nanocomposites

“…Recently, alumina-aluminum composite system has been developed by stir casting process and a secondary process of rolling was incorporated to improve the properties [22]. In a different investigation, hot-extrusion was applied after processing the composite by cold-press sintering [23].…”