|About this Abstract
||3rd World Congress on High Entropy Alloys (HEA 2023)
||Achieving Exceptional Mechanical Properties in High Entropy Alloys via Thermodynamically Guided Local Chemical Ordering
||Sriswaroop Dasari, Abhishek Sharma, Chao Jiang, Bharat Gwalani, Stephane Gorsse, An-Chou Yeh, Srinivasan Srivilliputhur, Rajarshi Banerjee
|On-Site Speaker (Planned)
Understanding the local chemical ordering propensity in random solid solutions, and tailoring its strength, can guide the design and discovery of complex, paradigm-shifting multi-component alloys. A simple thermodynamic framework was employed, based solely on binary enthalpies of mixing, to select optimal alloying elements to control the nature and extent of chemical ordering in high entropy alloys (HEAs). Subsequently, high resolution electron microscopy, atom probe tomography, and computational modeling have been coupled to demonstrate how controlled additions of Al and Ti and subsequent annealing drive chemical ordering (from short-range ordered domains to long-range ordered precipitates) in nearly random equiatomic FCC CoFeNi solid solution, boosting its tensile yield strength by a factor of four while also substantially improving ductility, which breaks the so-called strength-ductility paradox. The generality of this approach was demonstrated via addition of Al for introducing chemical ordering and enhancing mechanical properties in another nearly random BCC refractory NbTaTi HEA.
||Planned: Metallurgical and Materials Transactions