PSI - Issue 21

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

www.elsevier.com/locate/procedia

www.elsevier.com/locate/procedia

ScienceDirect

Procedia Structural Integrity 21 (2019) 120–129

© 2019 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 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers This work investiga ted the mechanica l and microstructura l effects of Portevin-LeCha telier bands in a luminum 5754 a lloy under different loading conditions. For these conditions (equibiaxia l and uniaxia l), an in-plane biaxia l test apparatus was utilized with a minia ture cruciform specimen. The amount and magnitude of load jumps and drops (serra tions) due to the PLC bands were monitored by load cells and st ra in distributions were measured by digita l image correla tion technique. Under biaxia l stretching, PLC bands nuclea ted and propaga ted repea tedly a t the same region of the sample, while their formation was random under uniaxia l tension. Overa ll contribution of PLC stra in to the tota l stra in was higher under equib iaxia l stretching, yet there were no v isib le shear bands as the PLC bands were suppressed. Conversely, the shear stress sta te in tension promoted PLC bands and evolved them into sharp shear bands. Texture ana lysis confirmed the emergence of shear components and cube texture with increasing stra in. The eventua l fa ilure of the sample was from the shear band(s). The ma in benefit of biaxia l loading was prevention of undesired fracture from shear bands, without changing the overa ll forming characteristics and the initia l copper texture of the ma teria l. © 2019 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 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials Investigation of Portevin-LeChatelier B nds in 5754 Aluminum Alloy under Various Strain Paths O. Berk Aytuna a , Mert Efe a* a Department of Metallurgical andMaterials Engineering, MiddleEast Technical University, Ankara 06800, Turkey Ab tract This work investiga ted the mechanica l and microstructura l effects of Portevi -LeCha telier bands in a luminum 5754 a lloy under different loading conditions. For th se conditions (equibiaxia l and uniaxia l), an in-plan biaxia l test apparatus w s utilized with a minia ture cruciform specimen. The amount and magnitude of load jumps and drops (serra ti ns) due to the PLC bands were monito ed by loa cells nd st ra in distributions were measured by digita l image cor ela tion techniq e. Under ia ia l stretc in , PLC bands nuclea ted and propaga ted repea tedly a t the sam region of the sample, while their formation was random under uniaxia l tensio . Overa ll contribution of PLC stra in to the tota l stra in was higher under quib iaxia l stretching, yet there were no v isib le sh ar bands as th PLC bands wer suppressed. Conversely, the she r stress sta te in tension promoted PLC bands and evolved them into sharp shear band . Texture ana lysis confi med the emergen e of shear components and cube tex u e with i creasing stra in. The eventua l fa ilure of the sample was from the shear band(s). The ma in benefit of biaxia l loading was prevention of undesired fracture from shear bands, without changing the overa ll forming characteristics and the initia l copper texture of the ma teria l. © 2019 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 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials Investigation of Portevin-LeChatelier Bands in 5754 Aluminum Alloy under Various Strain Paths O. Berk Aytuna a , Mert Efe a* a Department of Metallurgical andMaterials Engineering, MiddleEast Technical University, Ankara 06800, Turkey Abstract Keywords: PLC; Cruciform; DIC; Biaxial; Forming

Keywords: PLC; Cruciform; DIC; Biaxial; Forming

* Corresponding author. Tel.:+90-312-210-5925; fax:+90-312-210-2518. E-mail address: mefe@metu.edu.tr

2452-3216 ©2019TheAuthors. Published byElsevier B.V. This is an open access article under the CCBY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/ Peer-review under responsibility of the 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers 2452-3216 ©2019TheAuthors. Published byElsevier B.V. This is an open access article under the CCBY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/ Peer-review under responsibility of the 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers * Corresponding author. Tel.:+90-312-210-5925; fax:+90-312-210-2518. E mail address: m fe@metu.edu.tr

2452-3216 © 2019 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 1st International Workshop on Plasticity, Damage and Fracture of Engineering Materials organizers 10.1016/j.prostr.2019.12.093