Effect of elemental interaction on microstructure of CuCrFeNiMn high entropy alloy system

CuCrFeNiMn alloy system with different elemental contents is synthesized by using the arc melting and casting method. Effect of elemental interaction on microstructure of these alloys is investigated by means of Ni equivalent and Cr equivalent. The alloys exhibit quite simple solid solution phases with FCC or FCC + BCC mixed structures. Bimodal distribution and peak shift in XRD patterns resulted from the lattice constants difference of FCC phase are observed in most alloys. The formation of simple solid solution phase is associated with the slight difference in atomic size and properly mixing enthalpy. The Cu, Mn, Cr and Fe are mostly segregated in dendrite or interdendrite regions, while the Ni is homogeneously distributed in the alloys. In addition, alloys with higher Ni equivalent principally consist of single FCC phase; while those with higher Cr equivalent are mainly composed of FCC + BCC mixed structures. (C) 2009 Elsevier B.V. All rights reserved.