Microstructure and properties of high-entropy alloy reinforced aluminum matrix composites by spark plasma sintering

An CoCrFeMnNi high-entropy alloy (HEA) particles reinforced 2024Al alloy composite was prepared by spark plasma sintering (SPS). There is an interdiffusion (ID) layer between the HEA particle and the matrix. The composition and micromechanical properties of the diffusion layer were investigated by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), electron probe and nanoindentation. The unique element distribution in the diffusion layer and the obvious creep phenomenon are related to the sintering mode. The hardness of the composite is increased 63.7%, which was attributed to particle reinforcement and the relative low content of sintering defects in the matrix. •High-entropy alloy particles reinforced Al-based alloy composites were prepared by SPS.•The composite contains an interdiffusion (ID) layer, is about 6 μm thickness.•A new phase generated in the ID layer, affected by the enhanced diffusion reaction.•The ID layer appears obvious creep phenomenon, related to deceased atoms bonding force.