Plastic instabilities during processing of AlMg alloy

Scientific paper - Preliminary note / Short communication

• Author: Lorena Mrkobrada
• Author: Ivan Jandrlić
• Author: Franjo Kozina
• Author: Tin Brlić
• Author's institution: University of Zagreb; Faculty of Metallurgy
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy; Mechanical Metallurgy

Abstract (english)

During the plastic deformation of most metallic materials, the normal material flow takes place in part of the material, which we call deformation zone. There are some exceptions in certain alloys where process of plastic deformation is unstable and there is inhomogeneous plastic flow at certain parameters of plastic processing. Examples of such instabilities are the inhomogeneous plastic deformations such as Lűders bands and the Portevin-Le Chatelier effect, which appear in the form of deformation bands. Instabilities like these cause problems during metal processing into final products. The focus of this research was to determining the type of instability in received AlMg alloy. Visualization of material flow, displacement and deformation measurement during the static tensile test was performed using the DIC method. From results of tensile tests, repetitive serrations on the stress-strain curve during plastic deformation were observed. DIC analysis showed inhomogeneous deformation during the test, which lead to reasonable assumption that the observed instability was Portevin-Le Chatelier effect. To investigate the mechanisms of deformation, microstructures were recorded on samples before, during and after propagation by PLC band. Structural analysis showed that the deformation takes place through the movement of dislocations, which is indicated by their increased density at the PLC front and behind front after it passes.

• Keywords (english): plastic instabilities; AlMg alloy; Portevin Le Chatelier effect; Digital Image Correlation.
• Language: english
• Publication type: Scientific paper - Preliminary note / Short communication
• Publication status: Submitted
• Peer review: Peer review - international
• Publication version: Published version
• Publication title: 663rd IFC Portoroz 2023: conference proceedings
• ISBN: 978-961-94793-8-4
• URN:NBN: urn:nbn:hr:115:649800
• Publication: 2023-09
• Conference: Title: 63rd International Foundrymen Conference PORTOROZ 2023; Location: Portorož, Slovenia; Organizer: Slovenian Foundrymen Society; Start date: 2023-09-13; End date: 2023-09-15; Assembly type: Lecture
• Type of resource: Text
• Publisher: Ljubljana: Slovenian Foundrymen Society
• Access conditions: Open access
• Created on: 2024-04-24 11:41:38