Deformation twinning structure and interface in a FCC-based Al0.3FeNiCo1.2CrCu high-entropy alloy matrix composites

High entropy alloy composites (HEACs), Al0.3FeNiCo1.2CrCu reinforced by Titanium carbide (TiC) particles were produced by mechanical alloying (MA) and spark plasma sintering (SPS). The results from X-ray diffraction (XRD) and transmission electron microscopy (TEM) shows that a single FCC solid-solution phase with certain nanoscale deformation twins are produced following SPS. Subsequent investigations characterize the mechanical properties and microstructure of nanocrystalline twin HEAs by high resolution electron microscope (HREM) and compression tests. The produced interface was found to be clear and well bonded. The compressive yield strength, fracture strength, plastic strain and hardness are found to be 1730 ± 15 MPa, 2260 ± 15 MPa, 29.50% and 645Hv, respectively. This is attributed to the twin strengthening and the presence of uniformly distributed TiC particles.