Role of Grain Boundary Character on Dynamic Recrystallization (Morse, Poole, Corolewski, Stifter, Beck, Fritchman)
Computer simulations and experiments are used to study the role of grain boundary character on dynamic recrystallization (DRX). We are focused on the role of triple junction character during the early stages of nucleation. Monte Carlo simulations show how the kinetics of DRX change with varying initial populations of special grain boundaries. Experimentally, we are producing samples that have different starting microstructures and characterizing their deformation and microstructural evolution during DRX.
FUNDING: NATIONAL SCIENCE FOUNDATION
Fabrication of W-Based Alloys and Composites using Pulsed Electric Current Sintering (Sparks)
In collaboration with Idaho National Laboratory and the Center for Advanced Energy Studies, we are exploring the microstructural evolution of W-based alloys (e.g., W-Re) and composites (e.g., W-CeO2) materials for nuclear fuel applications using pulsed electric current sintering (PECS). PECS allows for fabrication of these materials at lower temperatures and for shorter times as compared to traditional processing routes. The PECS facility is at the Center for Advanced Energy Studies in Idaho Falls, ID.
COLLABORATORS: D. BUTT (BSU), I. CHARIT (U. IDAHO), M. CARROLL (INL)
FUNDING: U.S. DEPARTMENT OF ENERGY
High Temperature Mechanical Behavior and Microstructural Evolution in Heat Exchanger Alloys (Albiston)
The next generation nuclear plant (NGNP) will require heat exchangers that can operate at temperatures up to 900°C. Therefore, the alloys that are being considered (Ni-based alloys 617 and 230) must be proven to have good mechanical properties and microstructural stability during prolonged exposure to such operating conditions. In partnership with Idaho National Laboratory and MIT, we are studying the mechanical behavior of these alloys. Boise State is doing high temperature crack growth experiments on alloy 617 in air. In addition, we are performing microstructural characterization of materials after testing in impure He environments.
COLLABORATORS: R. WRIGHT (INL), R. BALLINGER (MIT)
FUNDING: U.S. DEPARTMENT OF ENERGY
Powder Processing of Amorphous Tungsten‐Based Alloys and Composites (Livers)
The objective of this project is to fabricate W-based amorphous metal matrix composites that have very high strength. The team at MIT will identify binary and ternary alloys, and process these into amorphous powders. The Boise State team is responsible for the consolidation of powders (primarily through pulsed electric current sintering) and the characterization of consolidated parts. Future work will include mechanical testing under both quasi-static and high strain rate conditions.
COLLABORATORS: C. SCHUH (MIT), L. MAGNESS, B. SCHUSTER (ARL)
FUNDING: DTRA