Прогнозування фазово-структурного стану литих сплавів з високою ентропією

• Дата: 2026
• Автор: Likhatskyi, I. F.
• Формат: Стаття
• Опубліковано: Physico- Technological Institute of Metals and Alloys of the NAS of Ukraine 2026
• Теми: складні концентровані сплави; ВЕС; сплави з пониженою густиною; лиття; мікроструктура; фазоутворення; термодинамічні параметри; SEM
• Онлайн доступ: https://momjournal.org.ua/index.php/mom/article/view/2026-2-1
• Назва журналу: Metal Science and Treatment of Metals

The structural and chemical heterogeneity of two Al-based complex concentrated alloys Al–Cr–Mn–Fe–Ni–Cu and Al–Cr–Mn–Fe–Co–Ni–Cu–Zn was investigated in the as-cast condition in order to evaluate the predictive capability of commonly used high-entropy alloy (HEA) descriptors. Integral thermodynamic parameters (ΔSmix, ΔHmix, δ, VEC, Ω, Δχ) calculated for both compositions fall within ranges typically considered favorable for solid-solution formation in HEA and complex concentrated alloys. In particular, ΔHmix and δ satisfy empirical stability criteria, while Ω exceeds commonly proposed thresholds for solid-solution formation. However, microstructural characterization reveals that these descriptors alone do not reliably predict the actual phase constitution in as-cast state. SEM/EDS analysis showed that both systems form a chemically heterogeneous dendritic-like morphology, accompanied by pronounced chemical partitioning between chemically distinct microstructural regions. In the Al–Cr–Mn–Fe–Ni–Cu alloy, two chemically distinct microstructural constituents were identified; however, both of them may correspond to B2-type intermetallic phases with a BCC-related lattice. Although VEC values fall within ranges associated with BCC or mixed BCC/FCC tendencies in Al-rich multicomponent alloys, experimental evidence indicates that the dominant structural constituents correspond to ordered intermetallic phases rather than disordered solid solutions. In contrast, the Al–Cr–Mn–Fe–Co–Ni–Cu–Zn alloy exhibits significantly higher chemical and morphological heterogeneity. Addition of Co and Zn leads to increased microstructural complexity and decrease of Cu-driven chemical separation. Local enrichment in Cu and Zn was detected in chemically distinct regions, indicating a strong tendency toward chemical separation and suggesting the formation of brass-type intermetallic phases.