J. Mater. Sci. Technol. ›› 2023, Vol. 153: 120-127.DOI: 10.1016/j.jmst.2022.12.047

• Research Article • Previous Articles     Next Articles

Serrated flow in NaI:Tl scintillator crystals

Jamieson Brechtla,*, Xie Xieb, Rui Fengb, Gongyao Wangb, Charles Melcherb,c, Mariya Zhuravlevab,c, Peter K. Liawb,*   

  1. aThe Bredesen Center for Interdisciplinary Research and Graduate Education, The University of Tennessee, Knoxville, TN 37996, USA;
    bDepartment of Materials Science and Engineering, The University of Tennessee, Knoxville, TN 37996, USA;
    cScintillation Materials Research Center, The University of Tennessee, Knoxville, TN 37996, USA
  • Received:2022-07-26 Revised:2022-12-03 Accepted:2022-12-09 Published:2023-08-01 Online:2023-02-28
  • Contact: *E-mail addresses: jbrechtl@vols.utk.edu (J. Brechtl), pliaw@utk.edu (P.K. Liaw).

Abstract: The serrated-flow behavior is an important phenomenon that unveils material-deformation mechanisms, as reported for various kinds of materials. NaI doped with Tl (NaI:Tl) is unique among scintillation materials in that the structure contains glide planes that are linked to serration behavior. In the present work, single crystals of NaI:Tl were subjected to room-temperature compression experiments at different strain rates. The serrated flow was observed, and complexity and multifractal analyses were performed to analyze the serration behavior. The findings revealed that the strain rate had a pronounced effect on the complexity and multifractality of the serrated flow, similar to what has been found in other alloy systems. The results also indicate that there may be a strong link between the complexity of the serrated flow behavior and the heterogeneity of the underlying dynamics. It is expected that the present work could be a step toward a better understanding of the deformation behavior and forgeability of NaI:Tl single crystals.

Key words: Dislocations, Ceramic material, Mechanical testing, Numerical algorithms, Scintillator