PSI - Issue 61

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ScienceDirect

Procedia Structural Integrity 61 (2024) 164–170 Structural Integrity Procedia 00 (2024) 000–000 Structural Integrity Procedia 00 (2024) 000–000

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© 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of IWPDF 2023 Chairman © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of IWPDF 2023. Keywords: strain gradient plasticity; amorphous plasticity; strain localization; size e ff ect. Abstract Amorphous materials lack a defined crystalline structure, exhibiting a disordered atomic arrangement that imparts superb me chanical properties and great potential for applications in many areas. Because of their disordered nature, metallic glasses exhibit dramatically di ff erent deformation behaviours than crystalline materials. A common example which stems from their heteroge neous, disordered nature is the formation of prominent shear bands. These shear bands represent narrow zones where complex strain patterns emerge due to intense shear stress. Understanding the deformation characteristics of amorphous materials remains an ongoing goal that has not yet been fully accomplished. Recent experimental observations indicate that the shear band localization is delayed or even suppressed by reducing the sample size hinting at a size-dependent phenomenon. Therefore, a size-dependent model is required to fully uncover the underlying micromechanical phenomenon. In this regard, this study focuses on the numerical modelling of disorder within amorphous materials in a contiuum setting. To this end, a lower-order strain gradient plasticity (SGP) framework is employed to numerically analyze and discuss the size e ff ect on microstructure evolution in metallic glasses. To ob tain strain patterning, two distinct approaches were utilised and compared. Shear band formations under di ff erent types of loading scenarios are modelled and analyzed. Di ff erent sized specimens are studied and compared against the classical local plasticity solutions. © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of IWPDF 2023. Keywords: strain gradient plasticity; amorphous plasticity; strain localization; size e ff ect. 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Strain Gradient Plasticity Analysis of Amorphous Plasticity Izzet Erkin U¨ nsal a , Tuncay Yalc¸inkaya a, ∗ a Department of Aerospace Engineering, Middle East Technical University, Ankara 06800, Tu¨rkiye Abstract Amorphous materials lack a defined crystalline structure, exhibiting a disordered atomic arrangement that imparts superb me chanical properties and great potential for applications in many areas. Because of their disordered nature, metallic glasses exhibit dramatically di ff erent deformation behaviours than crystalline materials. A common example which stems from their heteroge neous, disordered nature is the formation of prominent shear bands. These shear bands represent narrow zones where complex strain patterns emerge due to intense shear stress. Understanding the deformation characteristics of amorphous materials remains an ongoing goal that has not yet been fully accomplished. Recent experimental observations indicate that the shear band localization is delayed or even suppressed by reducing the sample size hinting at a size-dependent phenomenon. Therefore, a size-dependent model is required to fully uncover the underlying micromechanical phenomenon. In this regard, this study focuses on the numerical modelling of disorder within amorphous materials in a contiuum setting. To this end, a lower-order strain gradient plasticity (SGP) framework is employed to numerically analyze and discuss the size e ff ect on microstructure evolution in metallic glasses. To ob tain strain patterning, two distinct approaches were utilised and compared. Shear band formations under di ff erent types of loading scenarios are modelled and analyzed. Di ff erent sized specimens are studied and compared against the classical local plasticity solutions. 3rd International Workshop on Plasticity, Damage and Fracture of Engineering Materials (IWPDF 2023) Strain Gradient Plasticity Analysis of Amorphous Plasticity Izzet Erkin U¨ nsal a , Tuncay Yalc¸inkaya a, ∗ a Department of Aerospace Engineering, Middle East Technical University, Ankara 06800, Tu¨rkiye

1. Introduction 1. Introduction

Amorphous materials, such as bulk metallic glasses (BMGs), are produced by rapid cooling of liquid materials to prevent crystallization, having garnered significant interest for their outstanding mechanical properties and wide ranging applications in aerospace, microelectronics, micro-electromechanical systems (MEMS), biomedical devices and implants, microrobotics, and micromanipulators (Kumar et al. (2011)). Although they lack crystalline structure in the traditional sense, BMGs have been discovered to exhibit a solid-like yield phenomenon. At room temperature, Amorphous materials, such as bulk metallic glasses (BMGs), are produced by rapid cooling of liquid materials to prevent crystallization, having garnered significant interest for their outstanding mechanical properties and wide ranging applications in aerospace, microelectronics, micro-electromechanical systems (MEMS), biomedical devices and implants, microrobotics, and micromanipulators (Kumar et al. (2011)). Although they lack crystalline structure in the traditional sense, BMGs have been discovered to exhibit a solid-like yield phenomenon. At room temperature,

∗ Corresponding author. Tel.: + 90 312 210 4258 ; fax: + 90 312 210 4250. E-mail address: yalcinka@metu.edu.tr ∗ Corresponding author. Tel.: + 90 312 210 4258 ; fax: + 90 312 210 4250. E-mail address: yalcinka@metu.edu.tr

2452-3216 © 2024 The Authors. Published by ELSEVIER B.V. This is an open access article under the CC BY-NC-ND license (https://creativecommons.org/licenses/by-nc-nd/4.0) Peer-review under responsibility of the scientific committee of IWPDF 2023 Chairman 10.1016/j.prostr.2024.06.022 2210-7843 © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of IWPDF 2023. 2210-7843 © 2024 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http: // creativecommons.org / licenses / by-nc-nd / 4.0 / ) Peer-review under responsibility of the scientific committee of IWPDF 2023.