About this Abstract |
Meeting |
2022 TMS Annual Meeting & Exhibition
|
Symposium
|
Advances in Multi-Principal Elements Alloys X: Structures and Modeling
|
Presentation Title |
Beyond Configurational Entropy: A Harmonic Multi-principal Elements Alloy |
Author(s) |
Zhaowei Wan, Subramamyan Pattamatta, Jian Han, David Joseph Srolovitz |
On-Site Speaker (Planned) |
David Joseph Srolovitz |
Abstract Scope |
High entropy alloys are substitutional solid solutions of multiple principal elements. “High entropy" refers to the high configurational entropy associated with randomly occupying lattice sites with different elements. The high strength of these alloys is associated with misfit stresses generated by random site occupancies. Here, we examine the effect of random misfit in a model system where bonds are harmonic and equilibrium bond lengths drawn from a Gaussian distribution. We demonstrate that harmonic lattices of single bond length atoms shrink upon heating (negative thermal expansion). We then demonstrate that bond length randomness is isomorphic to randomness associated with atomic vibrations. We exploit this “exact” analogy to determine the entropy associated with random misfit and show how to map between temperature and misfit randomness in the determination of lattice parameter and elastic constants. We exploit this approach to examine temperature-independent lattice parameters (invar) and elastic constant (elinvar) through misfit tuning. |
Proceedings Inclusion? |
Planned: TMS Journal: Metallurgical and Materials Transactions |
Keywords |
High-Entropy Alloys, Modeling and Simulation, Other |