| Summary: | 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.
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