The influence of iron impurities on the compression behaviour of Al-2.24Mg-2.09Li alloy

Scientific paper - Original scientific paper

• Author: Franjo Kozina
• Author: Zdenka Zovko Brodarac
• Author's institution: University of Zagreb; Faculty of Metallurgy; (Department of Process Metallurgy); (Laboratory of Iron, Steel and Founding)
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Metallurgy; Process Metallurgy

Abstract (english)

As a major impurity element in aluminium-lithium (Al-Li) alloys, iron (Fe) reduces formability, fracture toughness, and
fatigue resistance by solidifying into Al6Fe and Al3Fe particles. The research was performed in order to estimate the
influence of Fe impurities on the compression behaviour of Al-2.24Mg-2.09Li alloy. The investigation was performed on
the samples in as cast and solution hardened condition. The solution hardening was applied to improve the mechanical
properties by dissolving intermetallic particles and enriching αAl matrix with Mg. However, the higher strength properties
and temperature increase during the compression testing were observed in as cast condition. Microstructural investigation
revealed significant differences in microstructure changes between the samples in as cast and solution hardened condition.
In as cast sample the barrelling effect led to the unequal deformation and surface texture development. The eutectic Al3Fe
particles located in the αAl interdendritic areas did not significantly impact microstructure changes. Although the solution
hardening led to enrichment of αAl matrix with Mg and Fe, the Al3Fe particles were not dissolved. The coarse morphology
of Al3Fe particles and location at the grain boundaries of αAl grains contributed to low energy intergranular fracture. The
fracture nucleation and propagation across the grain boundaries resulted in lower strength values.

• Keywords (english): Al-Mg-Li alloy; Iron impurities; Solution hardening; Compression testing; Microstructure; Low energy intergranular fracture
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review - international
• Publication version: Published version
• Journal title: Journal of Mining and Metallurgy, Section B: Metallurgy
• Numbering: vol. 56, no. 3, pp. 425-433
• p-ISSN: 1450-5339
• e-ISSN: 2217-7175
• DOI: https://doi.org/10.2298/JMMB200613038K
• URN:NBN: urn:nbn:hr:115:048278
• Publication: 2020
• Document URL: http://www.jmmab.com/images/pdf/2020/3/1450-53392000038K.pdf
• Type of resource: Text
• Access conditions: Open access
• Created on: 2021-10-01 06:41:43