Slow dynamic elastic recovery in unconsolidated metal structures

التفاصيل البيبلوغرافية
العنوان: Slow dynamic elastic recovery in unconsolidated metal structures
المؤلفون: Yoritomo, John Y., Weaver, Richard L.
المصدر: Phys. Rev. E 102, 012901 (2020)
سنة النشر: 2019
المجموعة: Condensed Matter
Physics (Other)
مصطلحات موضوعية: Condensed Matter - Soft Condensed Matter, Condensed Matter - Other Condensed Matter, Physics - Classical Physics
الوصف: Slow dynamic nonlinearity is widely observed in brittle materials with complex heterogeneous or cracked microstructures. It is seen in rocks, concrete and cracked glass blocks. Unconsolidated structures show the behavior as well: aggregates of glass beads under pressure and a single glass bead confined between two glass plates. A defining feature is the loss of stiffness after a mechanical conditioning, followed by a logarithmic-in-time recovery. Materials observed to exhibit slow dynamics are sufficiently different in microstructure, chemical composition, and scale (ranging from the laboratory to the seismological) to suggest some kind of universality. There lacks a full theoretical understanding of the universality in general and the log(time) recovery in particular; one suspicion has been that the phenomenon is associated with glassy grain boundaries and microcracking. Seminal studies were focused on sandstones and other natural rocks, but in recent years other experimental venues have been introduced with which to inform theory. Here, we present measurements on some simple metallic systems: an unconsolidated aggregate of aluminum beads under a confining pressure, and an aluminum bead confined between two aluminum plates, and a steel bead confined between steel plates. Ultrasonic waves are used as probes of the systems, and changes are assessed with coda wave interferometry. Three different methods of low-frequency conditioning are applied; all reveal slow dynamic nonlinearities. Results imply that glassy microstructures and cracking do not play essential roles, as they would appear to be absent in our systems.
Comment: 19 pages, 13 figures
نوع الوثيقة: Working Paper
DOI: 10.1103/PhysRevE.102.012901
URL الوصول: http://arxiv.org/abs/1912.04227
رقم الأكسشن: edsarx.1912.04227
قاعدة البيانات: arXiv
الوصف
DOI:10.1103/PhysRevE.102.012901