Engineering topics

Tegtmeier, Eric Lee

Publications and source records attributed to Tegtmeier, Eric Lee.

4 records

DOE OSTI2023

Investigation of Carbide Inclusions in Cast Uranium [Slides]

Outline - Introduction: The motivations for the project, and some background on inclusions in uranium, and about the samples; Lath Inclusion Morphology: Looking at the morphology of a specific family of carbide inclusions in casting 20; Clustering of Lath Inclusions: Investigating the group behavior of these lath shaped inclusions from the inner to outer edges; Conclusions: Final thoughts on the lath inclusions and future work ideas.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

DOE OSTI2023

U-rich U-Mo Solidus, Liquidus, Enthalpy, and Thermal Diffusivity

Several material properties have been studied as a function of composition as part of the USHPRR effort to use U-10Mo for LEU monolithic fuel foils, with special attention to areas where simulation outcomes can be improved. The liquidus and solidus phase boundaries are important for engineering design of processing parameters and for predicting the degree of microsegregation within initial castings. The numerous phase diagram constructions available in the literature differ significantly in their solid/liquid boundary definitions, therefore, an experimental strategy was employed in order to resolve some of the discord. That strategy focuses not on proving any singular point, but instead to provide data with highly characterized uncertainty. The data presented here is the most consistent with the U-rich liquidus and solidus boundaries provided by H. Okamoto (2012), Berche et al. (2011), and Mardon et al. (1959). The recently suggested change in the peritectic reaction temperature (to 1302 K) suggested by Berchè and adopted by Okamoto is also supported, but with lower confidence. The enthalpy of fusion is a basic characteristic of the solidification reaction property for which is required for both research-oriented predictions of behavior and development of applied design strategies for casting engineering. It has been determined that an admixture model for the heat of fusion between U BCC and Mo BCC is a reasonable assumption within the composition region of interest, though limitations of the measurement accuracy impacts the ability to support any trends more detailed than this baseline behavior. A limited number of thermal diffusivity measurements were also performed into the gamma region to provide additional information for solidification modeling and simulations as well as a check on the component properties of thermal conductivity, density, and heat capacity.

36 MATERIALS SCIENCE↗

DOE OSTI2022

EDEN Tube Interface Characterization Report

In 2022 Eden Radioisotopes and Los Alamos National Laboratory entered into a Creative Research and Development Agreement (CRADA) leveraging the metallography capabilities of the Characterization and Special Projects Team of Sigma-2 at LANL. EDEN identified a need to characterize the condition of metallic interfaces within their product created at different pressure conditions to see which processing parameters achieved interfaces within specifications for intended use. A total of 4 samples were sent to the Characterization Projects team and 3 were later sent to another facility (MST-7) where Micro CT was performed.

36 MATERIALS SCIENCE↗

DOE OSTI2022

Progress Towards a Titanium-Zirconium-Molybdenum Alloy Coreblock Prototype Using Powder Bed Fusion

Microreactor designs make use of a coreblock for structural stability allowing for these devices to provide powder generation while being portable and inherently safe. In order to maximize energy output of the microreactors, materials must be able to withstand high temperature without melting and without substantial decreases in mechanical properties. As simultaneous projects looking at steels, graphite, and other materials are on-going, this work package will investigate titanium – zirconium – molybdenum alloy (TZM) as it allows for potentially higher microreactor operating temperatures than traditional reactor materials such as stainless steel. Notably, this alloy was developed in the 1960s for use in rockets and has a very high melting point (2623°C) but is difficult to form, machine and join. With limited needs in aerospace, literature is appropriately sparce in looking at the AM of TZM (examples include [1,2]). However, the properties appear to be an excellent match for the needs of the microreactor coreblock leading to the current project. In addition, small washers form the bulk of TZM parts needed in aerospace while the microreactor community was looking at larger, more complex parts. Therefore, AM of TZM is being explored to enable near – net shape of components with the needed complexity to impact the nuclear energy field.

36 MATERIALS SCIENCE↗