Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions
Investigating the effect of Fe and Si is essential for any new Al-based composition, as these impurities can be easily found both after primary production and recycling. This study is dedicated to filling the gap in revealing the phase composition of an Al-6%Mg-2%Ca-2%Zn alloy after the combined and...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2023-09-01
|
| Series: | Metals |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2075-4701/13/9/1584 |
| _version_ | 1797578796783632384 |
|---|---|
| author | Vitali Doroshenko Pavel Shurkin Tatyana Sviridova Anastasiya Fortuna Ivan Shkaley |
| author_facet | Vitali Doroshenko Pavel Shurkin Tatyana Sviridova Anastasiya Fortuna Ivan Shkaley |
| author_sort | Vitali Doroshenko |
| collection | DOAJ |
| description | Investigating the effect of Fe and Si is essential for any new Al-based composition, as these impurities can be easily found both after primary production and recycling. This study is dedicated to filling the gap in revealing the phase composition of an Al-6%Mg-2%Ca-2%Zn alloy after the combined and separate addition of Fe and Si. This was addressed by permanent mold casting and solid solution heat treatment. The investigation of slowly solidified samples also contributed to understanding potential phase transitions. It was found that the alloy containing 0.5%Fe can have nearly spherical intermetallics after heat treatment, whereas a higher Fe content brought the formation of a needle-shaped Al<sub>3</sub>Fe intermetallic. We explain this by the formation of a ternary α-Al + Al<sub>10</sub>CaFe<sub>2</sub> + Al<sub>4</sub>Ca eutectic, which is more compact in as-cast condition compared to divorced binary α-Al + Al<sub>4</sub>Ca and α-Al + Al<sub>3</sub>Fe eutectics. Similarly, 0.5%Si readily incurred the formation of a needle-shaped Al<sub>2</sub>CaSi<sub>2</sub> intermetallic, probably also by a binary reaction L → α-Al + Al<sub>2</sub>CaSi<sub>2</sub>. In the solidified samples, no Mg<sub>2</sub>Si phase was found, even in slowly solidified samples. This is contrary to the thermodynamic calculation, which suggests a peritectic reaction L + Al<sub>2</sub>CaSi<sub>2</sub> Mg<sub>2</sub>Si. Interestingly, the addition of 0.5%Si caused an even coarser microstructure compared to the addition of 1%Fe, which caused the appearance of a primary Al<sub>3</sub>Fe phase. We conclude that the new alloy is more tolerable to Fe rather than Si. Specifically, the addition of 0.5%Fe can be added while maintaining a fine morphology of the eutectic network. It was suggested that the morphology of eutectic and solid solution hardening governed the mechanical properties. The strength of the alloys containing separate 0.5%Fe (UTS = 215 ± 8 MPa and YS 146 ± 4 = MPa) and the combined 0.5%Fe and 0.5%Si additions (UTS = 195 ± 14 MPa and YS ± 1 = 139 MPa) was not compromised compared to the alloy containing 0.5%Si (UTS 201 ± 24 = MPa and YS = 131 ± 1 MPa). |
| first_indexed | 2024-03-10T22:27:50Z |
| format | Article |
| id | doaj.art-41ae3643ecdc469584c3f0c6ecebbe5c |
| institution | Directory Open Access Journal |
| issn | 2075-4701 |
| language | English |
| last_indexed | 2024-03-10T22:27:50Z |
| publishDate | 2023-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Metals |
| spelling | doaj.art-41ae3643ecdc469584c3f0c6ecebbe5c2023-11-19T11:56:59ZengMDPI AGMetals2075-47012023-09-01139158410.3390/met13091584Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si AdditionsVitali Doroshenko0Pavel Shurkin1Tatyana Sviridova2Anastasiya Fortuna3Ivan Shkaley4Sector of Project Activities, Moscow Polytechnical University, Bolyshaya Semenovskaya Str. 38, 107023 Moscow, RussiaBrunel Centre for Advanced Solidification Technology (BCAST), Brunel University London, Middlesex, Uxbridge UB8 3PH, UKInstitute of New Materials and Nanotechnology, National University of Science and Technology MISIS, Leninsky Prospekt 4, 119049 Moscow, RussiaDepartment of Physical Materials Science, National University of Science and Technology MISIS, Leninsky Prospekt 4, 119049 Moscow, RussiaIshlinsky Institute for Problems in Mechanics RAS, Russian Academy of Sciences, 119526 Moscow, RussiaInvestigating the effect of Fe and Si is essential for any new Al-based composition, as these impurities can be easily found both after primary production and recycling. This study is dedicated to filling the gap in revealing the phase composition of an Al-6%Mg-2%Ca-2%Zn alloy after the combined and separate addition of Fe and Si. This was addressed by permanent mold casting and solid solution heat treatment. The investigation of slowly solidified samples also contributed to understanding potential phase transitions. It was found that the alloy containing 0.5%Fe can have nearly spherical intermetallics after heat treatment, whereas a higher Fe content brought the formation of a needle-shaped Al<sub>3</sub>Fe intermetallic. We explain this by the formation of a ternary α-Al + Al<sub>10</sub>CaFe<sub>2</sub> + Al<sub>4</sub>Ca eutectic, which is more compact in as-cast condition compared to divorced binary α-Al + Al<sub>4</sub>Ca and α-Al + Al<sub>3</sub>Fe eutectics. Similarly, 0.5%Si readily incurred the formation of a needle-shaped Al<sub>2</sub>CaSi<sub>2</sub> intermetallic, probably also by a binary reaction L → α-Al + Al<sub>2</sub>CaSi<sub>2</sub>. In the solidified samples, no Mg<sub>2</sub>Si phase was found, even in slowly solidified samples. This is contrary to the thermodynamic calculation, which suggests a peritectic reaction L + Al<sub>2</sub>CaSi<sub>2</sub> Mg<sub>2</sub>Si. Interestingly, the addition of 0.5%Si caused an even coarser microstructure compared to the addition of 1%Fe, which caused the appearance of a primary Al<sub>3</sub>Fe phase. We conclude that the new alloy is more tolerable to Fe rather than Si. Specifically, the addition of 0.5%Fe can be added while maintaining a fine morphology of the eutectic network. It was suggested that the morphology of eutectic and solid solution hardening governed the mechanical properties. The strength of the alloys containing separate 0.5%Fe (UTS = 215 ± 8 MPa and YS 146 ± 4 = MPa) and the combined 0.5%Fe and 0.5%Si additions (UTS = 195 ± 14 MPa and YS ± 1 = 139 MPa) was not compromised compared to the alloy containing 0.5%Si (UTS 201 ± 24 = MPa and YS = 131 ± 1 MPa).https://www.mdpi.com/2075-4701/13/9/1584Al-Ca alloysironsiliconphase compositioneutecticintermetallic compounds |
| spellingShingle | Vitali Doroshenko Pavel Shurkin Tatyana Sviridova Anastasiya Fortuna Ivan Shkaley Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions Metals Al-Ca alloys iron silicon phase composition eutectic intermetallic compounds |
| title | Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions |
| title_full | Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions |
| title_fullStr | Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions |
| title_full_unstemmed | Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions |
| title_short | Phase Composition and Microstructure of Cast Al-6%Mg-2%Ca-2%Zn Alloy with Fe and Si Additions |
| title_sort | phase composition and microstructure of cast al 6 mg 2 ca 2 zn alloy with fe and si additions |
| topic | Al-Ca alloys iron silicon phase composition eutectic intermetallic compounds |
| url | https://www.mdpi.com/2075-4701/13/9/1584 |
| work_keys_str_mv | AT vitalidoroshenko phasecompositionandmicrostructureofcastal6mg2ca2znalloywithfeandsiadditions AT pavelshurkin phasecompositionandmicrostructureofcastal6mg2ca2znalloywithfeandsiadditions AT tatyanasviridova phasecompositionandmicrostructureofcastal6mg2ca2znalloywithfeandsiadditions AT anastasiyafortuna phasecompositionandmicrostructureofcastal6mg2ca2znalloywithfeandsiadditions AT ivanshkaley phasecompositionandmicrostructureofcastal6mg2ca2znalloywithfeandsiadditions |