Hi. My name is Alex deJong and I’m a PhD student in the Hufnagel group in the  Department of Materials Science and Engineering at Johns Hopkins University. 

I work with high and medium entropy alloys, also known as complex concentrated alloys. These are alloys that consist of 3 or more elements in near equal portions that form a single phase. The metallurgy community has taken an interest in discovering new alloys and characterizing their properties and performance. 

 Alloys from the Cantor alloy system offer favorable mechanical properties at extreme temperatures. Studies often point to lattice distortions in complex concentrated alloys as a contributor to their strength. The lattice distortion effect suggests that having atoms of different elements neighboring one another would result in a strained lattice that contributes to solid solution strengthening. Previous efforts for quantifying lattice distortions have employed the use of simulations and diffraction from polycrystalline samples. In contrast, we are collecting diffuse scattering patterns from single crystal complex concentrated alloys to quantify and explore the lattice distortion effect in 3-dimensional space.  

 We start by synthesizing single crystals composed of a few complex concentrated alloys derived from the commonly studied Cantor alloy. This is accomplished here at Johns Hopkins at the PARADIM user facility. We then take these single crystals to the QM2 beamline at the Cornell High Energy Synchrotron Source to collect high quality reciprocal space maps. The extraction and analysis of the diffuse scattering from these reciprocal space maps will assist in quantifying the lattice distortions and elucidate the structure to properties relationship for these alloy systems.