| About this Abstract |
| Meeting |
Materials Science & Technology 2020
|
| Symposium
|
High Entropy Materials: Concentrated Solid Solution, Intermetallics, Ceramics, Functional Materials and Beyond
|
| Presentation Title |
Control of Discontinuous and Continuous Precipitation of Gamma-prime Strengthened High-entropy Alloys |
| Author(s) |
Lei Fan, Zengbao Jiao |
| On-Site Speaker (Planned) |
Zengbao Jiao |
| Abstract Scope |
Precipitation of coherent L12-type gamma-prime precipitates has been recognized as a powerful method to strengthen fcc high-entropy alloys (HEAs) at room and elevated temperatures. Continuous precipitates are primarily responsible for precipitation hardening, whereas discontinuous precipitates contribute a limited hardening capability and often crack grain boundaries. In this talk, we show that minor alloying additions can have a significant effect on the precipitation behavior and mechanical properties of HEAs. The alloying additions not only suppress the discontinuous L12 precipitation through grain boundary segregation but also promote the continuous L12 precipitation through solute partitioning, which leads to a uniform distribution of L12 nanoparticles throughout the matrix, thereby enhancing the mechanical properties of the HEAs. The mechanisms for the suppression of discontinuous precipitation and promotion of continuous precipitation are discussed. |