The influence of the cooling rate on the phase composition and properties of multicomponent AlCoCrFeNiV alloys with the addition of Mn and Si

Purpose. This paper is devoted to studying the mechanical properties and structure of multicomponent high-entropy alloys of the AlCoCrFeNiV system with the addition of Mn and Si in as-cast and splat-quenched state. Design / Method / Approach. The as-cast ingots of AlCoCrFeMnNiSiV multicomponent samples were prepared using a Tamman furnace under an argon atmosphere. The alloy films were fabricated using the well-known splat-quenching technique. The cooling rate, estimated based on the film thickness, was ~10⁶ K/s. Findings. It has been established that the as-cast alloys have a multiphase structure, which includes solid solutions with a BCC lattice and ordered solid solutions of the B2 structural type, whereas the rapidly quenched alloys contain only disordered BCC solid solutions. It has been shown that the increase in the level of microstresses and dislocation density during rapid solidification contributes to the improvement of the mechanical properties of the studied alloys. The enhanced strength characteristics are due to the significant distortion of the crystal lattice caused by differences in the atomic radii of the elements. Theoretical Implications. This study advances the theoretical understanding of high-entropy alloys by explaining the relationship between cooling rates and the resulting phase structures and mechanical properties.  Practical Implications. With an increase in cooling rate, the dislocation density, level of microstrains and microhardness of the AlCoCrFeMnNiSiV multicomponent alloys increase. Originality / Value. This study provides novel insights into the phase composition and mechanical properties of multicomponent alloys with varying cooling rates. The research highlights the distinct structural differences between as-cast and splat-quenched alloys. Research Limitations / Future Research. The current study is limited by the scope of cooling rates and alloy compositions investigated. Future research could explore a broader range of cooling rates and additional alloying elements. to further understand their effects on the phase composition and properties of high-entropy alloys.