Abstract Scope |
High entropy alloys (HEAs), with their exceptional mechanical, physical, and chemical properties, have gained attention as potential structural materials. Notably, their excellent high temperature strength, corrosion and oxidation resistance, thermal stability, and magnetic properties make them appealing. However, recent research has revealed a strength-ductility trade-off, especially in HEAs with a single FCC structure, limiting their engineering applications. To address this, our study investigated non-equiatomic FeMnCoCr HEA containing 2 at% Si. The alloys were prepared by arc melting high purity elements, and their microstructure and mechanical properties were examined at room and cryogenic temperatures. Si alloying facilitated sigma phase formation during recrystallization annealing, impacting the stability and stacking fault energy of the FCC matrix. Consequently, multiple strain-induced deformation mechanisms were activated, leading to a transition from TRIP to TWIP deformation mode in the presence of 2 at% Si in the HEA matrix induced by the sigma phase. |