Thermal and Structural Analysis of a High-Entropy Cr16Mn16Fe16Co16Ni16P20 Alloy—Influence of Cooling Rates on Phase Transformations

• Published in: Materials 2024-11, Vol.17 (23), p.5772
• Main Authors: Ziewiec, Krzysztof, Błachowski, Artur, Prusik, Krystian, Jasiński, Marcin, Ziewiec, Aneta, Wojciechowska, Mirosława
• Format: Article
• Language: English
• Subjects: Alloys; Cooling; Cooling rate; Corrosion resistance; Crystallization; Ductility; Electric arc melting; Entropy; Face centered cubic lattice; Glass; Heat detection; High entropy alloys; Influence; Melt spinning; Microstructure; Mossbauer spectroscopy; Phase transitions; Phosphorus; Plasma sintering; Rapid quenching (metallurgy); Scanning electron microscopy; Spectrum analysis; Structural analysis; Supercooling; Temperature; Thermal transformations; Thermodynamic properties; Thermography; Wear resistance
• ISSN: 1996-1944; 1996-1944
• DOI: 10.3390/ma17235772

This study investigates the influence of cooling rates on the microstructure and phase transformations of the high-entropy alloy Cr16Mn16Fe16Co16Ni16P20. The alloy was synthesized via arc melting and subjected to three cooling conditions: slow cooling (52 K/s), accelerated cooling after a short electric arc pulse (3018 K/s), and rapid quenching (10⁵–10⁶ K/s) using the melt-spinning method. The microstructures were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Mössbauer spectroscopy. The thermal properties and phase transformations were analyzed using differential scanning calorimetry (DSC) and thermography. Slow cooling produced a complex crystalline microstructure, while accelerated cooling resulted in fewer phases. Rapid cooling yielded an amorphous structure, demonstrating that phosphorus and high mixing entropy enhance glass-forming ability. Phase transformations exhibited significant undercooling under accelerated cooling, with FCC phase crystallization shifting from 1706 K (slow cooling) to 1341 K, and eutectic crystallization from 1206 K to 960 K. These findings provide a foundation for optimizing cooling processes in high-entropy alloys for advanced structural and functional applications.