Seminar Notice for Zachary McClure's Preliminary Exam. Monday, Dec. 10, at 1:30, in ARMS 1028. Review Dec. 10, 2:30 - 3:00 in ARMS 2326; Exam Dec. 10, at 3:00, in ARMS 2326
Please consider attending the following: MATERIALS ENGINEERING SEMINAR “Thermal Transport Properties in Complex Nanostructured Metals: A Methodology Case Study” By Zachary D. McClure Purdue MSE Ph.D. Preliminary Exam Advisor: Professor Alejandro Strachan ABSTRACT Research attention towards reactive metal multilayers (RMM) has grown rapidly in the last 30 years. This class of energetic materials boast a well-controlled gas less exothermic reaction when primed that can be used for ignition mechanisms, lead-free soldering, and welding applications. The reaction mechanism of these multilayers involve an initial stimulus followed by a mixing of the alternating metallic layers. This mixing gives off heat and cascades into a self-propagating reaction front. The characteristics of this reaction front are determined by the exothermicity of the heat of mixing between metallic layers, and the thermal transport from the reaction site to unreacted material. Many multilayers have abrupt, sharp interfaces between layers, and thermal transport across the interface can be modeled using simple electron model approximations. However, in more recent years researchers have been finding classes of multilayers that pre-blend their interface prior to any thermal or mechanical stimulus. The amorphous regions between bulk crystalline layers can be beneficial or detrimental to thermal transport depending on the application. This review takes a computational approach for calculating the thermal transport characteristics of the amorphous alloy region. We will compare two different methods for calculating thermal conductivity in metallic glasses using the length dependent MD-Landauer approach, and variations of the Mott s-d model. The former boasts robust DFT calculations coupled with non-equilibrium Green’s functions to model transport across a device, and the latter considers the contributions between s and d-states of a glass for thermal transport. The two methods will be explored in detail, calculations will be done with each, and their results will be compared with initial experimental results from collaboration with Sandia National Laboratory (SNL) Date: Monday, December 10, 2018 Time: 1:30 P.M. Place: ARMS 1028
Please consider attending the following: MATERIALS ENGINEERING SEMINAR “Thermal Transport Properties in Complex Nanostructured Metals: A Methodology Case Study” By Zachary D. McClure Purdue MSE Ph.D. Preliminary Exam Advisor: Professor Alejandro Strachan ABSTRACT Research attention towards reactive metal multilayers (RMM) has grown rapidly in the last 30 years. This class of energetic materials boast a well-controlled gas less exothermic reaction when primed that can be used for ignition mechanisms, lead-free soldering, and welding applications. The reaction mechanism of these multilayers involve an initial stimulus followed by a mixing of the alternating metallic layers. This mixing gives off heat and cascades into a self-propagating reaction front. The characteristics of this reaction front are determined by the exothermicity of the heat of mixing between metallic layers, and the thermal transport from the reaction site to unreacted material. Many multilayers have abrupt, sharp interfaces between layers, and thermal transport across the interface can be modeled using simple electron model approximations. However, in more recent years researchers have been finding classes of multilayers that pre-blend their interface prior to any thermal or mechanical stimulus. The amorphous regions between bulk crystalline layers can be beneficial or detrimental to thermal transport depending on the application. This review takes a computational approach for calculating the thermal transport characteristics of the amorphous alloy region. We will compare two different methods for calculating thermal conductivity in metallic glasses using the length dependent MD-Landauer approach, and variations of the Mott s-d model. The former boasts robust DFT calculations coupled with non-equilibrium Green’s functions to model transport across a device, and the latter considers the contributions between s and d-states of a glass for thermal transport. The two methods will be explored in detail, calculations will be done with each, and their results will be compared with initial experimental results from collaboration with Sandia National Laboratory (SNL) Date: Monday, December 10, 2018 Time: 1:30 P.M. Place: ARMS 1028
participants (1)
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Son, Rosemary E