NE Colloquium: LTC Jon Baker
Title: "Remote Measurement of Multi-Axial Contraction Due to Pressureless Sintering."
Sintering of ceramic powders (non-metallic, inorganic compounds) is an important concept in the production of many commercial products including nuclear fuel pellets. Typically, industrial ceramic sintering involves forming (via pressing, extruding, slip-casting, etc.) ceramic powder into a green body shape that has at least ~40% solids content, and then sufficiently heating the green body to remove organic additives and produce the final consolidated product with a sought-after maximum density. During the sintering process, heat activates solid-state diffusional processes causing the granular microstructure to undergo changes that reduce surface energy by the formation of interparticle bonding, and consequentially, increased strength and densification of the entire product. During some sintering processes, the densification of the object is associated with significant shrinkage, which can be either dimensionally isotropic or anisotropic.
“Loose-powder sintering” (green body shape has ~ 10-40% solids content) is of primary interest in this dissertation because of possible relevance to fabrication of fast reactor fuel and porous ceramic filters. It is unconventional because the green body has a much lower solids content prior to heating. This purposely results in a final product with a lower bulk density. There are few industrial applications that make use of loose-powder sintering because it results in a significantly lower bulk density. Due to this, loose-powder sintering has not garnered devoted attention and is therefore not well understood. This research seeks to explore the behavior of loose-powder sintering via use of radiography-based dilatometry with the intent to determine if traditional Master Sintering Curve models can predict multiaxial sintering induced contraction response.
Lieutenant Colonel Jon Baker is an Assistant Professor at the United States Military Academy at West Point in the Department of Physics and Nuclear Engineering. He earned his PhD in Nuclear Engineering from the University of Tennessee in May 2020, an MS in Physics in 2010 from the University of Alabama in Huntsville, and a BS in Chemistry from USMA in 2001. His previous duties include teaching Physics at USMA, teaching the Nuclear Weapons Orientation Course and the Theater Nuclear Operations Course, and serving at USANCA. Before becoming a FA52 Nuclear/CWMD Officer, he served as an Army Aviator with both the 82nd Airborne Division and the 101st Airborne Division.
Zoom Meeting ID: 933 9681 2886
Wednesday, January 27 at 1:30pm to 2:30pmVirtual Event