PSI - Issue 17

Available online at www.sciencedirect.com Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000 Available online at www.sciencedirect.com ScienceDirect Structural Integrity Procedia 00 (2019) 000 – 000

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Procedia Structural Integrity 17 (2019) 906–913

ICSI 2019 The 3rd International Conference on Structural Integrity Experimental study of the influence of strain-stress state on the jerky flow in metals and alloys Tatyana Tretyakova a *, Valery Wildemann a a Centre of Experimental Mechanics, Perm National Research Polytechnic University, 29 Komsomolsky AVE, Perm 614990, Russia ICSI 2019 The 3rd International Conference on Structural Integrity Experimental study of the influence of strain-stress state on the jerky flow in metals and alloys Tatyana Tretyakova a *, Valery Wildemann a a Centre of Experimental Mechanics, Perm National Research Polytechnic University, 29 Komsomolsky AVE, Perm 614990, Russia

Abstract Abstract

This work is concerned with improvement of experimental methods for studying the influence of the stress-strain state on the spatial time inhomogeneity die to the jerky flow of Al-Mg alloys and carbon steels. The implementation of a complex stress state is based on the use of specimens with special complicated geometry. Mechanical tests were carried out on uniaxial tension of plates with a rigid rim, in the working part of which biaxial tension and combined tension-compression loading is realized. Evolution of inhomogeneous strain and temperature fields were analyzed by using the digital image correlation technique and infrared thermography. Experimental data on the kinetics of initiation and development of the deformation bands due to the Chernov-Lüders behavior and Portevin-Le Chatelier effect in various types of stress-strain state of the material were obtained. This work is co cerned with improvement of experimental methods for studying the influe ce of the stress-strain state on the sp tial time inhomogeneity die to t e jerky flow of Al-M alloys and carbo steels. The implementation of a complex stress state is based on the use of sp cimens with special complicated g ometry. Mechanical tests were carried out on uniaxial tension of plates with a rigid rim, in the working part of which biaxial tension and combined tension-compression loading is realized. Evolution of inho ogeneous strain a d temperature fields were analyzed by using the digital image correlation technique a d infrared thermography. Experimental data on th kinetics f initiation and development of the deformation bands du to the Chernov-Lüders behavior and Portevin-Le Chatelier effect in various types of stress-strain state of the material were obtained.

© 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers.

Keywords: digital image correlation; infrared thermography; jerky flow; stress-strain state; Portevin-Le Chatelier effect. Keywords: digital image correlation; infrared thermography; jerky flow; stress-strain state; Portevin-Le Chatelier effect.

1. Introduction 1. Introduction

High reliability of structures and prevention of industrial accidents are determined by the availability of information about physical, mechanical and strength characteristics of used materials, considering the influence of real external actions, which cause the complex stressed state of material. Failure processes in metals and alloys are associated with changing in their structure and mechanical properties during loading. Effects of serrated yielding lead to a significant High reliability of structures and prevention of industrial accidents are determined by the availability of information about physical, mechanical and strength characteristics of used materials, considering the influence of real external actions, which cause the complex stressed state of material. Failure processes in metals and alloys are associated with changing in their structure and mechanical properties during loading. Effects of serrated yielding lead to a significant

2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 2452-3216 © 2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. * Correspon ing author. Tel.: +79124995960; fax: +73422198732. E-mail address: cem.tretyakova@gmail.com * Corresponding author. Tel.: +79124995960; fax: +73422198732. E-mail address: cem.tretyakova@gmail.com

2452-3216  2019 The Authors. Published by Elsevier B.V. Peer-review under responsibility of the ICSI 2019 organizers. 10.1016/j.prostr.2019.08.121