Design of oxygen-doped TiZrHfNbTa refractory high entropy alloys with enhanced strength and ductility

Iroc L., Tukac O., Tanrisevdi B., El-Atwani O., Tunes M., KALAY Y. E., ...Daha Fazla

Materials and Design, cilt.223, 2022 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 223
  • Basım Tarihi: 2022
  • Doi Numarası: 10.1016/j.matdes.2022.111239
  • Dergi Adı: Materials and Design
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Aerospace Database, CAB Abstracts, Chimica, Communication Abstracts, Compendex, INSPEC, Metadex, Veterinary Science Database, Directory of Open Access Journals, Civil Engineering Abstracts
  • Anahtar Kelimeler: Refractory High Entropy Alloys (RHEAs), CALPHAD, Nano-lamellar structures, Nanotwins, In-situ TEM, PRINCIPAL ELEMENT ALLOYS, SOLID-SOLUTION PHASE, MECHANICAL-PROPERTIES, TENSILE PROPERTIES, LOW-DENSITY, MICROSTRUCTURE, STABILITY, BEHAVIOR, DEFORMATION
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

© 2022Refractory high entropy alloys (RHEAs) are considered promising materials for high-temperature applications due to their thermal stability and high-temperature mechanical properties. However, most RHEAs have high density (>10 g/cm3) and exhibit limited ductility at low temperatures and softening at high temperatures. In this study, we show that oxygen-doping can be used as a new alloy design strategy for tailoring the mechanical behavior of the TiZrHfNbTa alloy: a novel low-density (7.98 g/cm3) ductile RHEA. Even though the material is a single-phase BCC with some oxides at room temperature, secondary BCC and HCP nano-lamellar structures start to form above 600 °C in addition to the nano-twins which are shown to be stable up to 1000 °C. This alloy shows superior strength and compressive ductility due to the nanoengineered microstructure. The present study sheds light on tailoring the strength-ductility balance in RHEAs by controlling the microstructure of novel RHEAs at the nanoscale via oxygen-doping.