VIRTUAL


 Thursday,  August 4,  2022

3:45 – 4:45 pm (MT)


Speaker: Prof. Levente Balogh

Department of Mechanical and Materials Engineering

Queen's University, Kingston, Canada


“Quantifying the complex microstructure of materials subjected to extreme conditions using X-ray/neutron diffraction”

 

Abstract: 

Novel manufacturing techniques and experiments investigating the response of materials to extreme conditions frequently produce samples having unique, metastable, often short-lived complex features the characterization of which can present a challenge.

X-ray and neutron diffraction are widely known to be the go-to method for accurately identifying the crystal structure of materials and for related characterization methods, such as quantifying the phase composition of a specimen, characterizing its crystallographic texture, etc.

An equally useful attribute of X-ray and neutron scattering is that the collected data also carries detailed information on the various crystallographic defects present in materials: dislocations, radiation-induced defects, grain/sub-grain boundaries, twinning and stacking faults. These various defects, the population of which are often referred to as the microstructure, are very strongly correlated to the mechanical properties of materials. Thus, the ability to quantitatively characterize the microstructure is crucial for the development and validation of predictive plasticity models, which in turn facilitates efficient designs required by modern day engineering applications.
The lecture will introduce the audience to the capabilities of whole pattern Diffraction Line Profile Analysis (DLPA), a modern tool for microstructure characterization based on first-principle physical models. It will be shown how this method can provide quantitative information of features such as dislocation density, radiation defects, sub-grain size even when these are part of convoluted, complex microstructures typically forming in Additively Manufactures or Shocked Materials.



Bio: 

Dr. Balogh is an Assistant Professor at the Department of Mechanical and Materials Engineering, Queen’s University, Kingston, ON, Canada and is also affiliated with the Arthur B. McDonald Canadian Astroparticle Physics Research Institute. He received a Ph.D. in Physics (Materials and Solid State Physics) from Eötvös Loránd University, Budapest, Hungary, and continued as a postdoctoral fellow at the Los Alamos National Laboratory (LANL). Before his role as assistant professor Dr. Balogh was employed as a Research Scientist at the Radiation Damage and Deformation Branch at the Canadian Nuclear Laboratories (CNL) in Chalk River, ON, Canada.  Dr. Balogh’s expertise lies in applying and developing advanced Xray/synchrotron and neutron diffraction-based techniques to characterize the structure and microstructure of materials. He is particularly interested in the characterization and quantification of lattice defect populations using diffraction techniques with focus on radiation induced damage in nuclear structural materials, and characterizing the convoluted microstructure of Additively Manufactured materials.