About this Abstract |
| Meeting |
MS&T26: Materials Science & Technology
|
| Symposium
|
Advances in Refractory High Entropy Alloys and Ceramics
|
| Presentation Title |
Thermodynamics of Mechanical Behavior in R-CCAs: Balancing Room-Temperature Tensile Ductility and High Temperature Strength |
| Author(s) |
Eric A. Lass |
| On-Site Speaker (Planned) |
Eric A. Lass |
| Abstract Scope |
Body-centered cubic (BCC) refractory compositionally complex alloys (R-CCAs) can generally be separated into two classes: 1) derivatives of the so-called Senkov alloy, HfNbTaTiZr; and 2) alloys containing Mo and/or W. Senkov-related alloys often possess measurable tensile ductility at room temperature (RT) but exhibit poor mechanical properties at temperatures above 1200 °C, while Mo- and W-containing alloys show good strength retention at elevated temperatures but almost no RT tensile ductility. There is little evidence for alloys with an intermediate balance of properties. This work explores the mechanical behavior of BCC R-CCAs from a thermodynamic perspective in search of a continuum between these two classes of alloys. We derive a ductility parameter that correlates with observed composition-ductility behavior better than any other ductility parameter reported to date. Alloys expected to reside in the space between the two R-CCA classes are also identified and experimentally investigated. |