Study on the Effect of Compositional Modulation of Fe<sub>50</sub>(CoCrNi)<sub>50−x</sub>Mo<sub>x</sub> Multi-Principal Alloys on Their Organization and Properties

本研究通过掺杂具有较大原子半径的元素钼(Mo)，设计Fe50(CoCrNi)50−xMox (x = 5, 9, 13)多主元合金体系，系统探究了Mo含量对合金微观组织与力学性能的调控作用。通过冷轧和热处理，获得部分再结晶异质结构，使得Fe50(CoCrNi)41Mo9合金在室温下表现出高屈服强度(1096 MPa)和优异的延展性(19.6%)，展示了强度和延展性的平衡增强。透射电镜(TEM)与电子背散射衍射(EBSD)分析进一步揭示了变形过程中位错在异质界面处的累积与动态再分配行为，为多主元合金的强韧化设计提供了新思路。In this study, we designed Fe50(CoCrNi)50−xMox (x = 5, 9, 13) multi-principal alloy system by doping molybdenum (Mo), which is an element with a large atomic radius, and systematically explored the modulation effect of Mo content on the microstructure and mechanical properties of the alloy. A partially recrystallized heterostructure was obtained by cold rolling and heat treatment, resulting in Fe50(CoCrNi)41Mo9 alloy exhibiting high yield strength (1096 MPa) and excellent ductility (19.6%) at room temperature, demonstrating a balanced enhancement of strength and ductility. Transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD) analyses further reveal the accumulation and dynamic redistribution behavior of dislocations at heterogeneous interfaces during the deformation process, which provides a new idea for the design of toughened multi-principal element alloys.