ABOUT
    Josh
    Kacher
    Associate Professor
    Member/Fellow:
    TMS
    404.894.2781
    Love 265

    Josh Kacher joined Georgia Tech’s Materials Science and Engineering department as an assistant professor in Fall of 2015. Prior to his appointment, he was a postdoctoral scholar at the University of California, Berkeley. There, he worked in collaboration with General Motors to understand the Portevin-le Chatelier effect in Al-Mg and with the navy to develop novel rhenium-replacement alloys. His research approach centered on applying in situ TEM deformation to understand the influence of local chemistry on the behavior of defects such as dislocations and twins. This was coupled with mesoscale characterization of the defect state using EBSD for multiscale characterization of the deformation processes.

    His PhD and Masters work similarly focused on applying multiscale electron microscopy techniques to understanding defect behavior in a variety of systems such as ion-irradiated stainless steels, materials at elevated temperatures, and Mg alloys for light-weight alloy development.

    Teaching Interests

    Professor Kacher’s teaching interests encompass core materials science and engineering concepts, including the mechanical behavior of materials, microstructural characterization, and failure mechanisms. His instructional approach integrates both undergraduate and graduate courses, emphasizing fundamental principles and experimental methods. Professor Kacher engages students in developing a deep understanding of material properties and their relationship to structure and processing. His teaching also supports interdisciplinary learning and prepares students for research and professional practice.

    Research Areas:
    Selected publications
    1. Y Yang, K Ding, T Zhu, J Kacher, O Pierron, The role of grain size distribution on the anomalous yielding of ultrafine-grained Au thin films, Scripta Materialia 275, 117178, 2026
    2. M Tian, J Cheng, N Afroze, Y Yang, A Khan, J Kacher, Ultra-thin plan-view lamella made by focused ion beam, Ultramicroscopy, 114250, 2025
    3. L Daza-Llanos, S Stangebye, EJ Lang, K Hattar, O Pierron, J Kacher, Influence of irradiation damage on stress-assisted grain growth in ultrafine grained Au thin films using in situ transmission electron microscopy mechanical testing, Materials Science and Engineering: A, 149256, 2025
    4. Y Su, T Phan, L Xiong, J Kacher, Grain boundary barrier strength and local stress evolution: Geometric compatibility effects and the curious case of twin boundaries, Acta Materialia, 121698, 2025
    5. Y Yang, K Ding, X Liu, T Zhu, J Kacher, O Pierron, In situ TEM measurement of strain rate-dependent activation volume of ultrafine-grained Au films, Acta Materialia, 121868, 2025
    Education
    • Ph.D., University of Illinois at Urbana-Champaign, 2012
    • M.S., Brigham Young University, 2009
    • B.S., Brigham Young University, 2008
    Research Interests

    Professor Kacher’s research focuses on understanding the mechanical behavior of materials through experimental and theoretical approaches. His work addresses topics such as the deformation and failure mechanisms in metals, microstructure-property relationships, and advanced characterization techniques. This research aims to elucidate fundamental material responses under various loading conditions, contributing to improved material design and performance. Professor Kacher’s investigations actively involve graduate and undergraduate researchers.

    Josh Kacher’s research group is interested in understanding the mechanical and corrosion behavior of materials in extreme environments. This includes understanding material deformation and failure in either ambient or aggressive environments as well as understanding how variations in microstructure influence local corrosion susceptibility.

    A common theme in the Kacher Lab research approach is the development and application of multiscale electron microscopy techniques, including EBSD-based techniques for rapid microstructure characterization and quantification at the mesoscale and in situ TEM experiments where defect interactions and chemical processes can be observed directly. Current research focuses include fatigue crack initiation and growth, localized corrosion attack and sensitization, microstructural effects in ductile fracture, and dislocation/grain boundary interactions in coarse and ultrafine-grained materials.