MPIE researcher wins Best Poster Award in the category “Material Sciences” at MC2021
Saba Ahmad, scientist in the research group “Advanced Transmission Electron Microscopy” in the department “Structure- and Nano- /Micromechanics of Materials” won the Best Poster Award at this year’s “Microscopy Conference 2021 (MC2021)”. Due to Covid travel restrictions the conference was held online.
How grain boundaries effect materials’ properties
Ahmad investigates grain boundaries (GB) by atomic resolution scanning transmission electron microscopy (STEM), which are the interfaces separating differently oriented crystals and are one of the most important defects in polycrystalline materials. Previous studies suggest that the distinct atomic nature of grain boundaries controls their properties like mobility, cohesive strength and sliding resistance, which in turn have an enormous impact on the bulk properties and are responsible for various material processes in polycrystalline materials such as abnormal grain growth, stress corrosion cracking, high temperature deformation and inter-granular fracture, etc.
In this study, Ahmad and her colleagues established a direct correlation between the atomic structure of different structural states of Σ3  tilt GBs and their effect on excess properties by using advanced transmission electron microscopy techniques in combination with molecular statics and density functional theory simulations. STEM investigations revealed that despite having the same macroscopic degrees of freedom, two different microstates of the Σ3  (211) GBs are present in aluminium. The simulation methodologies revealed that the two microstates could originate from different local stress states present at the interfaces, which result in differing interfacial excess properties. This could ultimately influence material properties such as GB migration at high temperature, GB segregation, etc. The work was presented in form of a poster at the MC2021 conference.
The Microscopy Conference 2021
The MC2021 brings leading experts as well as emerging young researchers from all over Europe and overseas together. Furthermore, it aims at highlighting new developments in instrumentation and methods as well as providing a forum for new directions in the fields of life and materials sciences.