About this Abstract |
Meeting |
MS&T23: Materials Science & Technology
|
Symposium
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Interface-mediated Phenomena in Structural Materials
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Presentation Title |
The Role of Interfaces on Second Phase Nucleation and Attendant Mechanical Response in Structural High Entropy Alloys |
Author(s) |
Sriswaroop Dasari, Abhishek Sharma, Bharat Gwalani, Deep Choudhuri, Srinivasan Srivilliputhur, Rajarshi Banerjee |
On-Site Speaker (Planned) |
Rajarshi Banerjee |
Abstract Scope |
Obtaining a fine scale second phase distribution in the concentrated solid solution matrix of High Entropy Alloys (HEAs), is often difficult owing to sluggish precipitation kinetics and limited heterogeneous nucleation sites. Often, the precipitation of equilibrium phases, e.g., ordered B2 or sigma phase, can be limited due to their high nucleation barrier for homogeneous precipitation within the face-centered cubic (FCC) matrix. This can lead to the competing homogeneous nucleation of a metastable ordered L12 phase which has a substantially lower nucleation barrier. Introducing different types of interfaces, grain boundaries, twin boundaries, and heterophase interfaces, can lower the nucleation barrier of the equilibrium ordered B2/sigma phases, leading to a homogeneous distribution of such strengthening precipitates. This leads to substantial increases in the strength and strain-hardening of while maintaining very good tensile ductility in these HEAs. The role of these ordered precipitates on the deformation mechanisms will also be addressed. |