ePrints@IIScePrints@IISc Home | About | Browse | Latest Additions | Advanced Search | Contact | Help

Shear Bands in Materials Processing: Understanding the Mechanics of Flow Localization from Zener's Time to the Present

Viswanathan, K and Yadav, S and Sagapuram, D (2021) Shear Bands in Materials Processing: Understanding the Mechanics of Flow Localization from Zener's Time to the Present. In: Applied Mechanics Reviews, 72 (6).

App-Mec-Rev_72_6.pdf - Published Version

Download (3MB) | Preview
Official URL: https://dx.doi.org/10.1115/1.4049353


Shear banding is a material instability in large strain plastic deformation of solids, where otherwise homogeneous flow becomes localized in narrow micrometer-scale bands. Shear bands have broad implications for materials processing and failure under dynamic loading in a wide variety of material systems ranging from metals to rocks. This year marks 75 years since the publication of Zener and Hollomon's pioneering work on shear bands (Zener and Hollomon, J Appl. Phys., 15, 22-32, 1944), which is widely credited with drawing the attention of the mechanics community to shear bands and related localization phenomena. Since this landmark publication, there has been significant experimental and theoretical investigation into the onset of shear banding. Yet, given the extremely small length and time scales associated with band development, several challenges persist in studying the evolution of single bands, postinitiation. For instance, spatiotemporal development of strain fields in the vicinity of a band, crucial to understanding the transition from localized flow to fracture, has remained largely unexplored. Recent full-field displacement measurements, coupled with numerical modeling, have only begun to ameliorate this problem. This article summarizes our present understanding of plastic flow dynamics around single shear bands and the subsequent transition to fracture, with special emphasis on the postinstability stage. These topics are covered specifically from a materials processing perspective. We begin with a semihistorical look at some of Zener's early ideas on shear bands and discuss recent advances in experimental methods for mapping localized flow during band formation, including direct in situ imaging as well as ex situ/postmortem analyses. Classical theories and analytical frameworks are revisited in the light of recently published experimental data. We show that shear bands exhibit a wealth of complex flow characteristics that bear striking resemblance to viscous fluid flows and related boundary layer phenomena. Finally, new material systems and strategies for reproducing shear band formation at low speeds are discussed. It is hoped that these will help further our understanding of shear band dynamics, the subsequent transition to fracture, and lead to practical "control" strategies for suppressing shear band-driven failures in processing applications. © 2021 BMJ Publishing Group. All rights reserved.

Item Type: Journal Article
Publication: Applied Mechanics Reviews
Publisher: American Society of Mechanical Engineers (ASME)
Additional Information: Copyright to this article belongs to American Society of Mechanical Engineers (ASME)
Keywords: Boundary layers; Dynamic loads; Elasticity; Fracture; Potential flow; Shear bands, Deformation of solids; Experimental methods; Localization phenomena; Material instability; Materials processing; Processing applications; Shear band formation; Theoretical investigations, Shear flow
Department/Centre: Division of Mechanical Sciences > Mechanical Engineering
Date Deposited: 27 Jan 2021 09:15
Last Modified: 27 Jan 2021 09:15
URI: http://eprints.iisc.ac.in/id/eprint/67838

Actions (login required)

View Item View Item