This study aimed at understanding the structure and properties of dual-phase eutectics in ternary, quaternary, and quinary alloys of the Al-Co-Cr-Fe-Ni system. The alloys at case were i) Ni₄₈Fe₃₄Al₁₈, ii) Ni₄₄Fe₂₀Cr₂₀Al_16, and iii) Ni_34.4Fe_16.4Co_16.4Cr_16.4Al_16.4. Samples in the form of cylindrical bars, diameter 10 mm × 150 mm, were produced by arc melting and suction casting from pure elements (>99.9 wt%). Bridgman solidification at low growth velocity was used to produce additional samples with large eutectic spacing and lamellae thickness of the two phases body-centered cubic (BCC)-B2 and face-centered cubic (FCC) in order to facilitate phase characterization by energy-dispersive X-ray analysis (scanning electron microscopy/energy-dispersive spectroscopy) and nano-indentation. In agreement with thermodynamic calculations, each of the phases was found to be multi-component and contain all alloying elements in distinct amounts. The mechanical properties of the individual phases were analyzed in relation to their composition using nano-indentation experiments. These measurements revealed some insights into “high-entropy effects” and their contribution to the elastoplastic response to indentation loading. Further analysis focused on as-cast as well as heat-treated samples comprising phase fraction measurements, micro-indentation, and miniature testing in three-point bending configuration. For optimum heat treatment conditions, a good balance of strength and ductility was obtained for each of the investigated alloys. Further work is necessary in order to assess their capability as structural materials.

这项研究旨在了解Al-Co-Cr-Fe-Ni系统的三元，四元和五元合金中的双相共晶结构和性能。情况下的合金为i）Ni ₄₈ Fe ₃₄ Al ₁₈，ii）Ni ₄₄ Fe ₂₀ Cr ₂₀ Al ₁₆和iii）Ni _34.4 Fe _16.4 Co _16.4 Cr _16.4 Al _16.4。通过电弧熔化和吸铸，由纯元素（> 99.9重量％）制成直径为10 mm×150 mm的圆柱状样品。使用低生长速度的Bridgman固化来生产具有大共晶间距和两相薄板厚度的两个样品，体心立方（BCC）-B2和面​​心立方（FCC）以便通过能量分散来表征相X射线分析（扫描电子显微镜/能量分散光谱）和纳米压痕。与热力学计算一致，发现每个相都是多组分的，并且包含不同量的所有合金元素。使用纳米压痕实验分析了各个相的机械性能及其组成。这些测量结果揭示了对“高熵效应”及其对压痕载荷弹塑性响应的贡献的一些见解。进一步的分析集中在铸态和热处理样品上，包括相分数测量，微压痕和三点弯曲配置的微型测试。为了获得最佳的热处理条件，每种研究合金均获得了强度和延展性的良好平衡。为了评估其作为结构材料的能力，需要做进一步的工作。为了获得最佳的热处理条件，每种研究合金均获得了强度和延展性的良好平衡。为了评估其作为结构材料的能力，需要做进一步的工作。为了获得最佳的热处理条件，每种研究合金均获得了强度和延展性的良好平衡。为了评估其作为结构材料的能力，需要做进一步的工作。