Simultaneous XEDS-EBSD Study of NiCoAlFeCu(Cr,Ti) Multi-Component Alloys

NiCoAlFeCu, NiCoAlFeCuCr, and NiCoAlFeCuCrTi high-entropy alloys are prepared by mechanical alloying and sintered at 1200 degrees C and a pressure of 1.5GPa for 3h. The alloys were characterized by X-ray diffraction (XRD), electron backscatter diffraction (EBSD), and X-ray energy dispersive spectrometry (XEDS). The phases found are mostly variants of the face centered cubic (fcc) phases (space group Fm3m), bcc (space group Im3m), and hexagonal (space group P6(3)/mmc). Adding Ti to the NiCoAlFeCuCr system has strong effects on the solubility of the elements in the different phases and increases dramatically the number of phases present. The use of EBSD and XEDS allowed identification of a cubic phase in NiCoAlFeCu samples, which cannot be identified by XRD alone, and confirmed its identification by XRD in NiCoAlFeCuCr samples. The spatial distribution of phases and the grain structure in the three different samples, measured by EBSD and XEDS, is reported.