Investigation of phases in Al23Co15Cr23Cu8Fe15Ni16 and Al8Co17Cr17Cu8Fe17Ni33 high entropy alloys and comparison with equilibrium phases predicted by Thermo-Calc

► High entropy alloys are investigated by three dimensional atom probe. ► The brittle Al23Co15Cr23Cu8Fe15Ni16 alloy decomposes into two body centred cubic phases. ► Ductile Al8Co17Cr17Cu8Fe17Ni33 shows two prominent face-centred cubic phases. ► Results are compared with equilibrium phases predicted by Thermo-Calc.