Dr Andrew Breen is a senior postdoctoral fellow and deputy group leader of the Engineering Microstructures group within the Transport and Infrastructure theme of the School of Materials Science & Engineering. Andrew received his PhD from USyd in 2014 where he remained as an atom probe support engineer until 2016. He then undertook a Humboldt Fellowship at the Max-Planck-Institut für Eisenforschung (Germany) to directly observe hydrogen in metals. In 2019, he returned to USyd as a Senior Postdoctoral Fellow in an AUSMURI funded project focused on understanding structure-property-processing relationships of additively manufactured alloys. In 2024 he transitioned into his current role. Andrew is a leading expert in microstructural characterisation, particularly advanced atom probe analysis techniques.