Influence of Ti on Structure, Tribology, and Corrosion of CoCrFeMnNiTi<sub>x</sub> High-Entropy Alloy

Bulut C., Yıldız F., VAROL T., Akçay S. B., Ergüder T. O.

JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE, 2025 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Basım Tarihi: 2025
  • Doi Numarası: 10.1007/s11665-025-11639-y
  • Dergi Adı: JOURNAL OF MATERIALS ENGINEERING AND PERFORMANCE
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, PASCAL, Aerospace Database, Applied Science & Technology Source, Aquatic Science & Fisheries Abstracts (ASFA), Chemical Abstracts Core, Communication Abstracts, Compendex, Computer & Applied Sciences, INSPEC, Metadex, Civil Engineering Abstracts
  • Anahtar Kelimeler: CoCrFeMnNiTix, high-entropy alloys, microstructure, powder metallurgy, wear
  • Karadeniz Teknik Üniversitesi Adresli: Evet

Özet

In this study, high purity Co-Cr-Fe-Mn-Ni-Ti powders were produced by mechanical alloying, hot pressed at 650 MPa, and then sintered at 1000 degrees C for 2 h. The microstructural, mechanical, tribological, and corrosion properties of Ti-free (HEA-Ti-0-B), 3% Ti-added (HEA-Ti-3-B), and 5% Ti-added (HEA-Ti-5-B) high-entropy alloys (HEAs) were systematically investigated. The changes in the mass of the alloy powder materials were evaluated as a function of temperature and time using thermogravimetric analysis (TGA). At 850 degrees C, the HEA-Ti-0-P powders exhibited a mass gain of approximately 15.82%, while HEA-Ti-3-P and HEA-Ti-5-P showed increases of 26.83 and 28.55%, respectively. As confirmed by TGA, the increasing Ti content in the alloy powders led to a decrease in oxidation resistance. Microstructural analysis revealed that HEA-Ti-0-B exhibited a single-phase FCC structure, whereas Ti-containing alloys formed intermetallic phases. Porosity increased with Ti content, reaching 13.97% in HEA-Ti-5-B. Ti addition significantly enhanced mechanical performance, with HEA-Ti-5-B exhibiting the highest hardness (348.82 HB), a 32.2% improvement over HEA-Ti-0-B, alongside a 15.93% lower wear rate and 43.1% reduction in friction coefficient. However, in 3.5% NaCl medium, corrosion resistance decreased with increasing Ti addition and corrosion rates increased from 23.21 mpy (HEA-Ti-0-B) to 37.27 mpy (HEA-Ti-5-B). These findings highlight the trade-off between mechanical strength and electrochemical stability in Ti-containing HEAs.