Home Phase transformation and property improvement of Al–0.6Mg–0.5Si alloys by addition of rare-earth Y
Article Open Access

Phase transformation and property improvement of Al–0.6Mg–0.5Si alloys by addition of rare-earth Y

  • Qin Xu , Chengyuan Guo , Zeyuan Zheng , Sen Zhang , Yanhui Cai , Xiaoqin Bi , Ying Fu EMAIL logo and Ruirun Chen EMAIL logo
Published/Copyright: April 12, 2025
Download Article (PDF)
Become an author with De Gruyter Brill
Submit Manuscript Author Information
Science and Engineering of Composite Materials
From the journal Science and Engineering of Composite Materials Volume 32 Issue 1

Abstract

Al–0.6Mg–0.5Si (wt%) alloys with varying Y contents are prepared, and effects of Y on the microstructure, electrical conductivity, and mechanical properties are investigated. The results show that Al–0.6Mg–0.5Si alloys are refined by addition of Y, and the average grain size is refined from 254 to 168 μm with the addition of Y content from 0 to 0.4 wt%. Addition of Y can lead to the formation of the AlSiY phase and AlFeSiMgY mixed phase as Y can react with elements such as Fe and Si in the alloy. The electrical conductivity of Al–0.6Mg–0.5Si alloys initially increases and subsequently decreases with increasing Y content. The electrical conductivity reaches its highest value of 54.3% IACS by addition of 0.3 wt% Y, which is improved by 4% compared with that without addition of Y. The tensile strength increases with increasing Y content, and the highest value is 154 MPa by addition of Y with 0.4 wt%, which is improved by 12.4%. Elongation of alloys initially increases and subsequently decreases with increasing Y content. The strength improvement of Al–0.6Mg–0.5Si alloys is mainly attributed to grain refinement and precipitation of granular and short rod-like secondary phases caused by the addition of Y into Al–0.6Mg–0.5Si alloys.

Keywords: microstructure; electrical conductivity; mechanical properties; Al–Mg–Si alloy; rare earth

1 Introduction

Al–Mg–Si alloys exhibit high specific strength, low price, good formability, and high electrical conductivity and have been widely used in aerospace, automotive, overhead power transmission lines, and other fields [1,2,3]. However, both higher electrical conductivity and mechanical properties, which are affected by precipitates in alloys, are required for Al–Mg–Si alloys used in the power industry such as overhead power transmission lines [4,5,6]. Researchers have proposed many methods to improve both the electrical conductivity and mechanical properties of Al–Mg–Si alloys by controlling precipitates formed in alloys, such as managing the Mg/Si ratio [7,8,9], micro-alloying by transition metal elements and rare-earth elements [10,11,12], and heat treatment under different conditions [13,14,15].

Rare-earth elements such as La and Ce show positive effects on aluminum alloys, and addition of rare-earth elements into aluminum alloys can change their microstructure, refine the grain size, improve the distribution of inclusion phases, and remove harmful impurities, such as Si and Fe from alloys, and thereby improve the electrical conductivity of aluminum alloys [16,17]. In recent years, micro-alloying of rare-earth elements has been extensively studied by researchers. Jiang et al. [18] found that addition of trace La can reduce the grain size of Al–Mg–Si alloys and promote precipitation of the Mg2Si phase and β′ phase, and thereby increase the tensile strength of the alloy. Zupanič et al. [19] reported the effect mechanism of Sc and Y on dispersions in the AA 6086 aluminum alloy and found that addition of Sc and Y resulted in the formation of the α-AlMnSi phase and nano-sized spherical L12 phases during the homogenization process of the dendrite center and consequently improve the strength of the alloy. Jia et al. [20] found that Al–9Si–0.5Mg alloys with addition of both Y and Sr show better mechanical properties than those of the alloy without any addition but lower than those of alloys with addition of Y alone, owing to the formation of massive blocks, decrease the amount of adsorbed hydrogen and increase the shrinkage porosity.

Rare-earth element Y shows very high chemical activity, and Al-Y is an immiscible binary system, thus the solid solubility of Y in Al alloys is very small. Therefore, addition of Y into aluminum alloys can not only refine grains of alloys and form intermetallic phases with elements such as Fe and Si in the alloy but also remove gases from the melt and purify the alloy melt. Researchers have conducted many studies on the influence of rare-earth Y on mechanical properties of Al–Mg–Si alloys. However, the distribution of Y in the aluminum melt, the effect of Y on the morphology and distribution of the secondary phase, and the effect of Y on the electrical conductivity of Al–Mg–Si alloys still need to be further studied. In this article, Al–0.6Mg–0.5Si (wt%) alloys with different Y contents (Y wt% = 0.1, 0.2, 0.3, 0.4) were prepared, characterization studies of the structure, mechanical properties, and electrical conductivity of alloys with different additions of Y were performed, and the influence of Y addition on the grain size and secondary phase morphology was systematically studied. The relationship between the microstructure, electrical conductivity, and mechanical properties was analyzed, and the mechanism of rare-earth element Y on aluminum alloys was expounded.

2 Experimental section

Al–0.6Mg–0.5Si (wt%) alloys with different amounts of the rare-earth element yttrium (Y wt% = 0, 0.1, 0.2, 0.3, and 0.4), named AMSZ0, AMSZ1, AMSZ2, AMSZ3, and AMSZ4, respectively, were prepared in a SG2-7.5-10-type resistance furnace. Raw materials were industrial pure Al blocks (99.9 wt%), industrial pure Mg particles (99.9 wt%), the Al–20Si (wt%) master alloy, and the Al–10Y (wt%) master alloy. Before melting, pure Al blocks were put into a furnace graphite crucible, which was preheated to 600°C. Then, the pure Al blocks were melted at 750°C and maintained for 2 h. After that, the Al–20Si master alloy and Al–10Y master alloy were added to the melts at 720°C. Then, the melt was fully stirred, and slag floating on the melt was removed after it was maintained at 720°C for 15 min. Pure Mg particles wrapped in the Al foil were added after the melt was heated to 750°C, and then the C2Cl6 refining agent was added to remove gas and slag from the melt. After the melt was fully stirred and slag was fully removed, it was poured into a heat resistant steel mold, which was preheated to 200°C, and cylindrical ingots with a size of Φ70 mm × 140 mm were obtained.

Three “dog bone” shaped samples with a size of 50 mm × 6 mm × 2 mm were cut from cylindrical ingots as tensile specimens. Tensile tests were performed at room temperature with a speed of 2 mm/min using a WDW-50 universal mechanical testing machine. Tensile strength of the alloys was tested at least three times, and the average was taken as the ultimate tensile strength and elongation of each alloy. Samples with a size of 20 mm × 20 mm × 2 mm were taken to measure the electrical conductivity of alloys, which was performed at room temperature using an RTS-11 metal four-probe tester. Each alloy was tested three times, and the average was taken as its electrical conductivity in IACS (International Annealed Copper Standard).

Samples for metallographic observation were first ground with sandpapers from 180# to 2000# and then mechanically polished with a diamond polishing solution with a particle size of 1.0 μm. Before observation, samples were etched using Keller’s reagent for 30 s and ultrasonically cleaned with alcohol. The macrostructure of alloys was observed by optical microscopy (OM, BX53M, Tokyo, Japan). The grain size of each alloy was calculated using Image Pro Plus with an average of 15 randomly selected grains. Microscopic morphologies of alloys were observed using a scanning electron microscope (FEI INSPECT F50) in backscattered mode. The chemical composition of different phases was detected by energy-dispersive spectroscopy (EDS). Fracture morphologies of tensile samples were observed by scanning electron microscopy (SEM) in secondary electron mode.

3 Results and discussion

3.1 Macrostructure characteristics

Figure 1 shows the macrostructure of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions. The results show that the Al–0.6Mg–0.5Si alloy without addition of Y is composed of various equiaxed grains with different sizes. After the addition of Y to the Al–0.6Mg–0.5Si alloy, the macrostructure of different alloys is significantly refined, and the structure of alloys with different Y additions becomes more uniform. Figure 2 shows the average grain size of alloys with different additions of Y. It is obvious that the grain size of alloys decreases with increasing Y additions. The average grain size of the AMSZ0 alloy without Y addition is 254 μm. By addition of 0.1 wt% Y to the AMSZ0 alloy, the average grain size of the AMSZ1 alloy is refined to 226 μm, which is 11.0% smaller than that of the AMSZ0 alloy. When the amount of added Y is increased to 0.4 wt% Y, the average grain size of the AMSZ4 alloy is obviously refined to 168 μm, which is 33.9% smaller than that of the AMSZ0 alloy.

Figure 1 Optical morphology of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions. (a) 0 wt%, (b) 0.1 wt%, (c) 0.2 wt%, (d) 0.3 wt%, and (e) 0.4 wt%.
Figure 1

Optical morphology of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions. (a) 0 wt%, (b) 0.1 wt%, (c) 0.2 wt%, (d) 0.3 wt%, and (e) 0.4 wt%.

Figure 2 Average grain size of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.
Figure 2

Average grain size of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.

Rare-earth Y is a surface-active element, and its solubility in aluminum alloys is significantly low. It is therefore easy to accumulate in the liquid phase in front of the solid–liquid interface during the solidification process of alloys and lead to solute redistribution. Therefore, component supercooling will occur in front of the solid–liquid interface, and the nucleation rate of alloys will be increased [21]. On the other hand, rare-earth Y added into aluminum alloys can accumulate at grain boundaries together with Si and Mg atoms and reduce Si and Mg atoms dissolving in melts. Thus, growth of Mg2Si will be limited and lead to the formation of fine Mg2Si particles dispersed in aluminum alloys [22]. Furthermore, rare-earth Y can react with other elements and form complex compounds like short rods or particles, which tend to accumulate at grain boundaries and prevent the growth of grains. Above all, addition of rare-earth Y into the Al–0.6Mg–0.5Si alloy can refine grains of the aluminum alloys.

3.2 Microstructure of alloys

Figure 3 shows the microstructure of Al–0.6Mg–0.5Si (wt%) alloys by adding different amounts of rare-earth element Y. EDS results of different phases shown in Figure 3 are listed in Table 1. The results show that numerous discontinuous rod-like coarse phases form at grain boundaries of the AMSZ0 alloy, as shown in Figure 3(a). Besides, some white secondary phase particles form inside grains of the alloy. EDS results show that the rod-like coarse phases at the grain boundary mainly consists of Si, Al, and little Mg, and the white particles inside the grains consists of Mg and Si. Therefore, the AMSZ0 alloy without addition of Y is mainly composed of eutectic Si, β-Al5FeSi, and Mg2Si [1]. In addition, most of the Mg2Si particles are dispersed in the grains of the alloy and few Mg2Si particles are accumulated at the grain boundaries, which play a dispersion strengthening role in improving the strength of alloys [8].

Figure 3 SEM images of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions. (a) 0 wt%, (b) 0.1 wt%, (c) 0.2 wt%, (d) 0.3 wt%, (e) 0.4 wt%, and (f) enlargement of the rectangular box in (c).
Figure 3

SEM images of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions. (a) 0 wt%, (b) 0.1 wt%, (c) 0.2 wt%, (d) 0.3 wt%, (e) 0.4 wt%, and (f) enlargement of the rectangular box in (c).

Table 1

EDS analysis at each point marked in Figure 4 (wt%)

Points Al Si Mg Fe Y
1 89.25 3.52 0.56 6.67 —
2 98.02 0.62 1.36 — —
3 97.90 1.38 0.47 0.08 0.17
4 97.71 1.25 0.64 — 0.40
5 89.85 2.93 0.5 — 6.72
6 95.23 1.66 0.56 0.96 1.59
7 88.52 2.76 0.44 — 8.28
8 91.30 1.71 0.48 — 6.51
9 90.57 2.27 0.50 6.34 0.32
10 94.09 2.16 0.56 3.19 —
11 95.56 1.73 0.53 0.69 1.49

A small amount of rod-like AlSiY phase forms at the grain boundary of the AMSZ1 alloy by addition of 0.1 wt% Y into the AMSZ0 alloy, and the granular AlSiY phase appears inside grains of the alloy, as shown in Figure 3(b). More secondary phases form inside the grains and at grain boundaries of the AMSZ2 alloy by addition of 0.2 wt% Y into the AMSZ0 alloy, as shown in Figure 3(c). EDS results show that the white granular phase inside the grains at point 5 is the AlSiY phase, the short rod-like and granular particles at point 6 are the AlFeSiMgY mixed phase, and the rod-like particles at point 7 are the AlSiY phase [23]. As shown in Figure 3(f), length of the rod-like AlSiY phase is about 15 μm, and the length of the AlFeSiMgY mixed phase is about 5 μm. Formation of the AlSiY phase is attributed to significant electronegativity difference of Y and Al and Si [24]. The granular and rod-like AlSiY particles dispersed inside the grains can pin dislocations and impede the dislocation motion [25].

More secondary phases form at grain boundaries and inside grains of the AMSZ3 alloy by addition of 0.3 wt% Y into the AMSZ0 alloy, as shown in Figure 3(d). EDS results of point 9 shows that rod-like and granular particles at grain boundaries of the alloy are the α-Al8Fe2Si phase. Therefore, the β-Al5FeSi phase in the aluminum alloy will transform into the α-Al8Fe2Si phase by addition of 0.3 wt% Y into the AMSZ0 alloy, and addition of Y into the aluminum alloy promotes transformation from the β-Al5FeSi phase to the α-Al8Fe2Si phase. More α-Al8Fe2Si phases are formed at the grain boundary, and more AlSiY phase particles form inside grains of the AMSZ4 alloy by addition of 0.4 wt% Y into the AMSZ0 alloy, as shown in Figure 3(e). In addition, EDS analysis in Table 1 shows that a small amount of Mg is detected in the AlSiY phase for alloys with addition of Y. As has been reported, solid solubility of Mg in aluminum alloys is relatively high, and thus Mg tends to exist in the form of solid solutions in the as-cast aluminum alloys [7].

In summary, more secondary phases form inside the grains and at grain boundaries by addition of more Y into aluminum alloys. Specifically, addition of Y into the Al–0.6Mg–0.5Si (wt%) alloy promotes the transformation of the coarse rod-like β-Al5FeSi phase inside grains into the short rod-like and granular α-Al8Fe2Si phase. Addition of Y into the Al–0.6Mg–0.5Si (wt%) alloy leads to the formation of granular and rod-like AlSiY particles in Al–0.6Mg–0.5Si (wt%) alloys with different additions of rare-earth element Y.

3.3 Electrical conductivity

Figure 4 shows the electrical conductivity of Al–0.6Mg–0.5Si (wt%) alloys with different Y contents. The results indicate that the electrical conductivity of alloys with different Y contents initially increases and subsequently decreases with increasing Y addition. The electrical conductivity of the AMSZ0 alloy without addition of Y is 52.2% IACS. The electrical conductivity of the AMSZ1 alloy with addition of 0.1 wt% Y is increased to 53.3% IACS, which is 2.1% higher than that of the AMSZ0 alloy. The electrical conductivity of the AMSZ2 alloy with addition of 0.2 wt% Y is 53.7% IACS and that of the AMSZ3 alloy with addition of 0.3 wt% Y reaches a maximum of 54.3% IACS, which is 4% higher than that of the AMSZ0 alloy. However, the electrical conductivity of the AMSZ4 alloy with addition of 0.4 wt% Y decreases to 53.6% IACS, which is still 2.6% higher than that of the AMSZ0 alloy.

Figure 4 Electrical conductivity of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.
Figure 4

Electrical conductivity of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.

The electrical conductivity of aluminum alloys is mainly affected by solid solution elements, secondary phase, grain boundaries, etc. [26,27,28]. As for the AMSZ0 alloy without addition of Y, most impurities such as Fe and Si elements in the AMSZ0 alloy exist in the form of solid solution atoms [29]. Therefore, lattice distortion of the alloy is serious, and the solid solution atoms have a strong scattering effect on electrons; thus, the electrical conductivity of the AMSZ0 alloy without addition of Y is the lowest. However, the rare-earth element Y can react with impurities such as Fe and Si in the alloy, so addition of Y into the AMSZ0 alloy can lead to the formation of AlSiY and the AlFeSiMgY secondary phase, as shown in Figure 3. This promotes the transformation of Fe and Si atoms from the solid solution state to the precipitated state in the alloy and reduces lattice distortion of the alloy and the scattering effect of solid solution atoms on electrons [1]. Therefore, we can say that the addition of Y has a positive effect in the improving electrical conductivity of aluminum alloys.

However, the electrical conductivity of the AMSZ4 alloy with addition of 0.4 wt% Y is lower than that of the AMSZ3 alloy with addition of 0.3 wt% Y. Addition of rare-earth element Y to aluminum alloys can refine the aluminum alloys and increase the grain boundaries of the aluminum alloys. As has been reported in Moraga et al. [30], the scattering effect on electrons for alloys with finer grain size and more grain boundaries is much stronger, which can reduce the electrical conductivity of the alloys. In addition, a large number of secondary phases will be precipitated from the alloys with higher additions of rare-earth element Y, and an increase of secondary phase particles will increase the scattering effect on electrons, thus the electrical conductivity of the alloys will be reduced.

Overall, the electrical conductivity increase of aluminum alloys caused by precipitation of solid solution atoms is smaller than the electrical conductivity decrease caused by the increase of grain boundaries and secondary phase particles. Therefore, the electrical conductivity of the alloys with excessive addition of rare-earth element Y will be reduced. Consequently, the electrical conductivity of the AMSZ3 alloy with addition of 0.3 wt% Y to the AMSZ0 alloy is optimal.

3.4 Mechanical properties

Figure 5 shows the tensile strength and elongation of Al–0.6Mg–0.5Si (wt%) alloys with different Y contents. The results show that tensile strength of the alloys increases with increasing Y content. The tensile strength of the AMSZ0 alloy without addition of Y is 137 MPa and the elongation is 23.1%. The tensile strength of the AMSZ1 alloy with addition of 0.1 wt%Y is 139 MPa, which is 1.5% higher than that of the AMSZ0 alloy. The elongation of AMSZ1 alloy is 24.3%. The tensile strength of the AMSZ2 alloy with addition of 0.2 wt% Y is 142 MPa, and the elongation is 25.1%. When addition of Y is increased to 0.3 wt%, the tensile strength of the AMSZ3 alloy is 151 MPa, which is 10.2% higher than that of the AMSZ0 alloy. The elongation of the AMSZ3 alloy reaches the highest value of 28.0%, which is 21.2% higher than that of the AMSZ0 alloy. However, the tensile strength of the AMSZ4 alloy with addition of 0.4 wt% Y reaches the highest value of 154 MPa and the elongation is 22.0%. The tensile strength of the AMSZ4 alloy is increased by 12.4% comparing with that of the AMSZ0 alloy.

Figure 5 Tensile strength and elongation of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.
Figure 5

Tensile strength and elongation of Al–0.6Mg–0.5Si (wt%) alloys with different Y additions.

Mechanical properties of alloys are mainly affected by solid-solution atoms, grain boundaries, and secondary phase [31,32]. Solid-solution atoms in alloys can lead to lattice distortion and prevent the movement of dislocations in the alloys. According to the Hall–Petch relationship (1) [25]:

(1) σ y = σ 0 + k y d − 1 / 2 ,

where σ y is the yield strength, σ 0 is the overall resistance of lattice to dislocation movement, k y is the constant related to grain boundaries, and d is the average grain size of alloys. As shown in Figure 3, the grain size of the alloys is finer with more Y, and there will be more grain boundaries in alloys with more Y; therefore, the strength of alloys with more Y will be higher according to formula (1). In addition, impurities such as Fe exist in the form of a long rod-like β-Al5FeSi phase in aluminum alloys without addition of Y. The coarse and sharp long rod-like β-Al5FeSi phase will lead to stress concentration and reduce mechanical properties of the alloys. After addition of Y into the alloys, active Y easily reacts with Si atoms and forms granular and short rod-like AlSiY phases, which can promote transformation from the coarse β-Al5FeSi phase into the short rod-like and granular α-Al8Fe2Si phase. The AlSiY phase and α-Al8Fe2Si phase in alloys with different additions of Y are distributed discontinuously along grain boundaries, as shown in Figure 3(b)–(e). The discontinuously distributed phases in the alloys can increase the ability of grain boundaries to prevent the dislocation movement, thereby increasing the strength of alloys [33].

Furthermore, grain refinement of the aluminum alloys by addition of Y can lead to more homogeneous deformation in alloys; thus, plasticity of the alloys will be enhanced and the elongation will be improved [34]. Otherwise, the coarse and sharp β-Al5FeSi phase can be eliminated by addition of Y, and the splitting effect on the alloys during the tensile tests is reduced, which can also improve the elongation of the alloys. However, excessive addition of Y into the aluminum alloy can lead to precipitation of more secondary phase in the alloys and decrease the elongation of the alloys, which will exceed the elongation improvement caused by grain refinement. Thus, the elongation of alloys will be decreased. So, elongation of the alloys with different additions of Y initially increases and subsequently decreases with increasing Y contents.

3.5 Fracture morphology

Figure 6 shows the tensile fracture morphology of Al–0.6Mg–0.5Si (wt%) alloys with different Y contents. The results show that some dimples with different shapes are formed on the fracture surface of the AMSZ0 alloy without addition of Y element, as shown in Figure 6(a). The EDS results of elliptical particles observed at the fracture surface (Figure 6(b)) are shown in Figure 6(g). The results indicate that the elliptical particle is the β-Al5FeSi phase. The large-sized β-Al5FeSi compounds tend to segregate at grain boundaries, which can lead to the formation of cracks, and intergranular fracture is formed inside the sample. In addition, plastic deformation occurs before fracture of the alloy, thus fracture of the AMSZ0 alloy is ductile type.

Figure 6 Tensile fracture morphology of the Al–0.6Mg–0.5Si (wt%) alloy with different Y additions: (a) 0 wt%, (b) enlarged area of the box in (a), (c) 0.1 wt%, (d) 0.2 wt%, (e) 0.3 wt%, (f) 0.4 wt%, and (g) EDS analysis of the granular phase in (b).
Figure 6

Tensile fracture morphology of the Al–0.6Mg–0.5Si (wt%) alloy with different Y additions: (a) 0 wt%, (b) enlarged area of the box in (a), (c) 0.1 wt%, (d) 0.2 wt%, (e) 0.3 wt%, (f) 0.4 wt%, and (g) EDS analysis of the granular phase in (b).

After adding Y to the AMSZ0 alloy, as shown in Figure 6(c)–(f), fracture morphology of the alloys is much flatter than that of the AMSZ0 alloy, and numerous dimples with a circular or elliptical shape form at the fracture surface. The fracture surface of alloys with addition of 0.3 wt% Y exhibits the most dimples with uniform size than alloys with other Y additions, as shown in Figure 6(e), and the tensile strength and elongation of the AMSZ3 alloy are the highest. Addition of Y into alloys can lead to the fracture morphology of alloys transforming from coarse and irregular dimples to small and uniform dimples, and thus the alloys have ductile fracture. Particles rich in rare-earth elements are also observed on the fracture surface of the alloys (Figure 6(f)), which can act as the core of micropore cracks. Microcracks will propagate selectively after a deformation force is applied to samples until crack sources of alloys are generated. As for samples with small and uniform dimples, more grain boundaries can prevent crack propagation after cracks propagate to grain boundaries and thereby improve the strength and elongation of alloys [35]. A large number of second-phase particles appeared in dimples of the alloy with addition of 0.4 wt% Y, as shown in Figure 6(f). The larger second-phase particles can split the matrix of the alloy when a deformation force is applied to the sample and lead to the formation of cracks in the alloy, which will reduce the elongation of the alloy [36].

4 Conclusions

  1. Addition of Y to Al–0.6Mg–0.5Si alloys can refine the grain size of alloys, and the grain size of different alloys decreases with increasing Y content. Y can react with elements such as Fe and Si in the alloys and lead to the formation of the rod-like and granular AlSiY phase and AlFeSiMgY mixed phase, which promote transformation from the coarse β-Al5FeSi phase to a short rod-like α-Al8Fe2Si phase.

  2. The electrical conductivity of Al–0.6Mg–0.5Si alloys with different additions of Y initially increases and subsequently decreases with increasing Y content. The electrical conductivity of the alloy with 0.3 wt% Y reaches its highest value of 54.3% IACS, which is 4% higher than that of the AMSZ0 alloy. Addition of Y can react with elements such as Fe and Si in alloys and lead to the formation of a secondary phase, thereby promoting Si atom transformation from the solid-solution state to the precipitation state, which can decrease the electron scattering effect caused by lattice distortion and therefore improve the electrical conductivity of alloys.

  3. The tensile strength of Al–0.6Mg–0.5Si alloys with different additions of Y increases and the elongation initially increases and subsequently decreases with increasing Y content. The tensile strength and elongation of alloy without addition of Y are 137 MPa and 23.1%, respectively. The tensile strength of alloy with 0.4 wt% Y reaches its highest value of 154 MPa, which is improved by 12.4% compared with that without addition of Y. Elongation of the alloy with 0.3 wt% Y reaches its highest value of 28.0%, which is improved by 21.2% compared with that without addition of Y. Addition of Y to the Al–0.6Mg–0.5Si alloy can refine grains of the alloy and promote the formation of granular and short rod-like secondary phases, thereby improving the tensile strength of the alloy.

tel: +86-451-86412394, fax: +86-451-86412394

Acknowledgements

All authors are grateful for the reviewer’s valuable comments that improved the manuscript.

  1. Funding information: This work was supported by the National Natural Science Foundation of China (Grant No. 52425401 and 52001114), Program for Science & Technology Innovation Talents in Universities of Henan Province (No. 23HASTIT022 and 2021GGJS064), and Scientific Research Fund of State Key Laboratory of Materials Processing and Die & Mould Technology (Grant No. P2023-005).

  2. Author contributions: All authors have accepted responsibility for the entire content of this manuscript and consented to its submission to the journal, reviewed all the results, and approved the final version of the manuscript. QX (First Author): Supervision, formal analysis, writing – review and editing. CYG: Investigation, writing – review and editing. ZYZ: Methodology, validation, data Curation. SZ: Writing – original draft. YHC: Formal analysis, supervision. XQB: Supervision, academic guidance. YF: Software, academic guidance. RRC (Corresponding Author): Conceptualization, funding acquisition, resources. All authors acknowledge full responsibility for the conceptualization of the study, submission of results, and preparation of the manuscript.

  3. Conflict of interest: The authors state no conflict of interest.

  4. Informed consent: Informed consent has been obtained from all individuals included in this study.

  5. Ethical approval: The conducted research was not related to either human or animal use.

  6. Data availability statement: The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request.

References

[1] Wang W, Pan Q, Jiang F, Yu Y, Lin G, Wang X, et al. Microstructure evolution and performances of Al–0.7Mg–0.6Si–0.2Ce–X (X=Sc, Y and Zr) alloys with high strength and high electrical conductivity. J Alloy Compd. 2022;895:162654.10.1016/j.jallcom.2021.162654Search in Google Scholar

[2] Meng F, Huang H, Yuan X, Lin X, Cui Z, Hu X. Segregation in squeeze casting 6061 aluminum alloy wheel spokes and its formation mechanism. China Foundry. 2021;18:45–51.10.1007/s41230-021-0079-xSearch in Google Scholar

[3] Zarif M, Spacil I, Pabel T, Schumacher P, Li J. Effect of Ca and P on the size and morphology of eutectic Mg2Si in high-purity Al–Mg–Si alloys. Metals. 2023;13(4):784.10.3390/met13040784Search in Google Scholar

[4] Li X, Cui X, Liu H, Zhu Z, Liu J, Zhang X, et al. Study on the improvement and mechanism of AA6101 electrical conductivity by trace TM (Zr, V, Ti) elements-assisted boron treatment. J Alloy Compd. 2023;939:168728.10.1016/j.jallcom.2023.168728Search in Google Scholar

[5] Zheng Y, Luo B, Xie W, Li W. Microstructure evolution and precipitation behavior of Al–Mg–Si alloy during initial aging. China Foundry. 2023;20(1):57–62.10.1007/s41230-023-1113-ySearch in Google Scholar

[6] Ye H, Cui X, Cui H, Li X, Zhu Z, Pan Y, et al. Study about improving mechanism of electrical conductivity of AA1070Al treated by a novel composite boron treatment with trace Ti. J Alloy Compd. 2021;870(2):159416.10.1016/j.jallcom.2021.159416Search in Google Scholar

[7] Nikzad Khangholi S, Javidani M, Maltais A, Chen XG. Optimization of mechanical properties and electrical conductivity in Al–Mg–Si 6201 alloys with different Mg/Si ratios. J Mater Res. 2020;35(20):2765–76.10.1557/jmr.2020.249Search in Google Scholar

[8] Jiang S, Wang R. Grain size-dependent Mg/Si ratio effect on the microstructure and mechanical/electrical properties of Al–Mg–Si–Sc alloys. J Mater Sci Technol. 2019;35(7):1354–63.10.1016/j.jmst.2019.03.011Search in Google Scholar

[9] Yang M, Chen H, Orekhov A, Lu Q, Lan X, Li K, et al. Quantified contribution of β″and β′ precipitates to the strengthening of an aged Al–Mg–Si alloy. Mater Sci Eng: A. 2020;774:138776.10.1016/j.msea.2019.138776Search in Google Scholar

[10] De Luca A, Dunand DC, Seidman DN. Microstructure and mechanical properties of a precipitation-strengthened Al–Zr–Sc–Er–Si alloy with a very small Sc content. Acta Mater. 2018;144:80–91.10.1016/j.actamat.2017.10.040Search in Google Scholar

[11] Liu YF, Jia XJ, Qiao XG, Xu SW, Zheng MY. Effect of La content on microstructure, thermal conductivity and mechanical properties of Mg–4Al magnesium alloys. J Alloy Compd. 2019;806:71–8.10.1016/j.jallcom.2019.07.267Search in Google Scholar

[12] Guo W, Chen X, Liu P, Yu G, Fu S, Fan J, et al. Effects of Er additions on the microstructure, mechanical properties, and electrical conductivity of the Al‐0.4 Fe‐0.05 Si alloy. Adv Eng Mater. 2021;23(3):2000955.10.1002/adem.202000955Search in Google Scholar

[13] Pozdniakov AV, Barkov RY. Microstructure and mechanical properties of novel Al–Y–Sc alloys with high thermal stability and electrical conductivity. J Mater Sci Technol. 2020;36:1–6.10.1016/j.jmst.2019.08.006Search in Google Scholar

[14] Zhang P, Li Y, Liu Y, Zhang Y, Liu J. Analysis of the microhardness, mechanical properties and electrical conductivity of 7055 aluminum alloy. Vacuum. 2020;171:109005.10.1016/j.vacuum.2019.109005Search in Google Scholar

[15] Onat A. Effects of artificial aging heat treatment on mechanical properties and corrosion behaviour of AA6XXX aluminium alloys. J Chem Eng Mater Sci. 2018;9(2):17–23.10.5897/JCEMS2018.0315Search in Google Scholar

[16] Zhang Y, Wei F, Mao J, Niu G. The difference of La and Ce as additives of electrical conductivity aluminum alloys. Mater Charact. 2019;158:109963.10.1016/j.matchar.2019.109963Search in Google Scholar

[17] Yuan WH, Liang ZY, Zhang CY, Wei LJ. Effects of La addition on the mechanical properties and thermal-resistant properties of Al–Mg–Si–Zr alloys based on AA 6201. Mater Des. 2012;34:788–92.10.1016/j.matdes.2011.07.003Search in Google Scholar

[18] Jiang H, Zheng Q, Song Y, Li Y, Li S, He J, et al. Influence of minor La addition on the solidification, aging behaviors and the tensile properties of Al–Mg–Si alloys. Mater Charact. 2022;185:111750.10.1016/j.matchar.2022.111750Search in Google Scholar

[19] Zupanič F, Žist S, Albu M, Letofsky-Papst I, Burja J, Vončina M, et al. Dispersoids in Al–Mg–Si Alloy AA 6086 modified by Sc and Y. Materials. 2023;16(8):2949.10.3390/ma16082949Search in Google Scholar PubMed PubMed Central

[20] Jia P, Hu X, Zhang JY, Teng XY, Gao GG, Zhao DG, et al. Strengthening effects of Y and Sr on Al–9Si–0.5 Mg alloy. Mater Res Express. 2018;6(1):016538.10.1088/2053-1591/aae631Search in Google Scholar

[21] Wang W, Pan Q, Wang X, Liu B. Improved heat and corrosion resistance of high electrical conductivity Al–Mg–Si alloys by multi-alloying of Ce, Sc and Y. Corros Sci. 2024;226:111695.10.1016/j.corsci.2023.111695Search in Google Scholar

[22] Esmaeili Ghayoumabadi M, Mochugovskiy AG, Tabachkova NY, Mikhaylovskaya AV. The influence of minor additions of Y, Sc, and Zr on the microstructural evolution, superplastic behavior, and mechanical properties of AA6013 alloy. J Alloy Compd. 2022;900:163477.10.1016/j.jallcom.2021.163477Search in Google Scholar

[23] Ding W, Zhao X, Chen T, Zhang H, Liu X, Cheng Y, et al. Effect of rare earth Y and Al–Ti–B master alloy on the microstructure and mechanical properties of 6063 aluminum alloy. J Alloy Compd. 2020;830:154685.10.1016/j.jallcom.2020.154685Search in Google Scholar

[24] Chen X, Li Q, Chen J, Zhu L. Microstructure and mechanical properties of Mg–Gd–Y–Sm–Al alloy and analysis of grain refinement and strengthening mechanism. J Rare Earths. 2019;37(12):1351–8.10.1016/j.jre.2018.12.014Search in Google Scholar

[25] Mao G, Yan H, Zhu C, Wu Z, Gao W. The varied mechanisms of yttrium (Y) modifying a hypoeutectic Al–Si alloy under conditions of different cooling rates. J Alloy Compd. 2019;806:909–16.10.1016/j.jallcom.2019.07.107Search in Google Scholar

[26] Han Y, Shao D, Chen BA, Peng Z, Zhu ZX, Zhang Q, et al. Effect of Mg/Si ratio on the microstructure and hardness–conductivity relationship of ultrafine-grained Al–Mg–Si alloys. J Mater Sci. 2017;52:4445–59.10.1007/s10853-016-0691-0Search in Google Scholar

[27] Bobruk EV, Safargalina ZA, Golubev OV, Baykov D, Kazykhanov VU. The effect of ultrafine-grained states on superplastic behavior of Al–Mg–Si alloy. Mater Lett. 2019;255:126503.10.1016/j.matlet.2019.126503Search in Google Scholar

[28] Zhao N, Ban C. Developing a high-strength Al–Mg–Si alloy with improved electrical conductivity by a novel ECAP route. Met Mater Int. 2022;28(10):2513–28.10.1007/s12540-021-01152-xSearch in Google Scholar

[29] Shuai GL, Li Z, Zhang DT, Tong YX, Li L. The mechanical property and electrical conductivity evolution of Al–Fe alloy between room temperature and elevated temperature ECAP. Vacuum. 2021;183:109813.10.1016/j.vacuum.2020.109813Search in Google Scholar

[30] Moraga L, Henriquez R, Solis B. Quantum theory of the effect of grain boundaries on the electrical conductivity of thin films and wires. Phys B: Condens Matter. 2015;470:39–49.10.1016/j.physb.2015.04.034Search in Google Scholar

[31] Ma PP, Liu CH, Chen QY, Wang Q, Zhan LH, Li JJ. Natural-ageing-enhanced precipitation near grain boundaries in high-strength aluminum alloy. J Mater Sci Technol. 2020;46:107–13.10.1016/j.jmst.2019.11.035Search in Google Scholar

[32] Zhang JX, Gao AH. Effect of micro-Y on microstructure and properties of Al–Mg–Si aluminum alloy. J Aeronaut Mater. 2012;32(1):6–9.Search in Google Scholar

[33] Liu Y, Meng S, Gao M, Pan S, Fu Y, Guan R. Enhanced comprehensive performance via alloying and rheo-diecasting in a semi-solid Al–Si–Fe–Mg–Cu–Sr alloy. J Mater Res Technol. 2023;25:420–39.10.1016/j.jmrt.2023.05.222Search in Google Scholar

[34] Liu X, Wang B, Li Q, Wang J, Zhang C, Xue C, et al. Quantifying the effects of grain refiners Al–Ti–B and La on the microstructure and mechanical properties of W319 alloy. Metals. 2022;12(4):627.10.3390/met12040627Search in Google Scholar

[35] Ibrahim MF, Abdelaziz MH, Samuel AM, Doty HW, Samuel FH. Effect of rare earth metals on the mechanical properties and fractography of Al–Si-based alloys. Int J Metalcast. 2020;14:108–24.10.1007/s40962-019-00336-xSearch in Google Scholar

[36] Wang X, Guan R, Zhang Y, Su N, Ji L, Li Y, et al. Microstructure evolution and properties of Al/Al–Mg–Si alloy clad wire during heat treatment. Appl Phys A. 2016;122:1–8.10.1007/s00339-016-0150-4Search in Google Scholar
Received: 2024-09-05
Accepted: 2024-11-15
Published Online: 2025-04-12

© 2025 the author(s), published by De Gruyter

This work is licensed under the Creative Commons Attribution 4.0 International License.

Articles in the same Issue

  1. Research Articles
  2. Investigation on cutting of CFRP composite by nanosecond short-pulsed laser with rotary drilling method
  3. Antibody-functionalized nanoporous silicon particles as a selective doxorubicin vehicle to improve toxicity against HER2+ breast cancer cells
  4. Study on the effects of initial stress and imperfect interface on static and dynamic problems in thermoelastic laminated plates
  5. Analysis of the laser-assisted forming process of CF/PEEK composite corner structure: Effect of laser power and forming rate on the spring-back angle
  6. Phase transformation and property improvement of Al–0.6Mg–0.5Si alloys by addition of rare-earth Y
  7. A new-type intelligent monitoring anchor system for CFRP strand wires based on CFRP self-sensing
  8. Optical properties and artistic color characterization of nanocomposite polyurethane materials
  9. Effect of 200 days of cyclic weathering and salt spray on the performance of PU coating applied on a composite substrate
  10. Experimental analysis and numerical simulation of the effect of opening hole behavior after hygrothermal aging on the compression properties of laminates
  11. Engineering properties and thermal conductivity of lightweight concrete with polyester-coated pumice aggregates
  12. Optimization of rGO content in MAI:PbCl2 composites for enhanced conductivity
  13. Collagen fibers as biomass templates constructed multifunctional polyvinyl alcohol composite films for biocompatible wearable e-skins
  14. Early age temperature effect of cemented sand and gravel based on random aggregate model
  15. Properties and mechanism of ceramizable silicone rubber with enhanced flexural strength after high-temperature
  16. Review Article
  17. State-of-the-art review on the influence of crumb rubber on the strength, durability, and morphological properties of concrete
  18. Special Issue: Advanced modeling and design for composite materials and structures
  19. Validation of chromatographic method for impurity profiling of Baloxavir marboxil (Xofluza)
https://doi.org/10.1515/secm-2024-0048
Keywords for this article
microstructure; electrical conductivity; mechanical properties; Al–Mg–Si alloy; rare earth
Creative Commons
BY 4.0

Articles in the same Issue

  1. Research Articles
  2. Investigation on cutting of CFRP composite by nanosecond short-pulsed laser with rotary drilling method
  3. Antibody-functionalized nanoporous silicon particles as a selective doxorubicin vehicle to improve toxicity against HER2+ breast cancer cells
  4. Study on the effects of initial stress and imperfect interface on static and dynamic problems in thermoelastic laminated plates
  5. Analysis of the laser-assisted forming process of CF/PEEK composite corner structure: Effect of laser power and forming rate on the spring-back angle
  6. Phase transformation and property improvement of Al–0.6Mg–0.5Si alloys by addition of rare-earth Y
  7. A new-type intelligent monitoring anchor system for CFRP strand wires based on CFRP self-sensing
  8. Optical properties and artistic color characterization of nanocomposite polyurethane materials
  9. Effect of 200 days of cyclic weathering and salt spray on the performance of PU coating applied on a composite substrate
  10. Experimental analysis and numerical simulation of the effect of opening hole behavior after hygrothermal aging on the compression properties of laminates
  11. Engineering properties and thermal conductivity of lightweight concrete with polyester-coated pumice aggregates
  12. Optimization of rGO content in MAI:PbCl2 composites for enhanced conductivity
  13. Collagen fibers as biomass templates constructed multifunctional polyvinyl alcohol composite films for biocompatible wearable e-skins
  14. Early age temperature effect of cemented sand and gravel based on random aggregate model
  15. Properties and mechanism of ceramizable silicone rubber with enhanced flexural strength after high-temperature
  16. Review Article
  17. State-of-the-art review on the influence of crumb rubber on the strength, durability, and morphological properties of concrete
  18. Special Issue: Advanced modeling and design for composite materials and structures
  19. Validation of chromatographic method for impurity profiling of Baloxavir marboxil (Xofluza)
Sign up now to receive a 20% welcome discount
Institutional Access
How does access work?
Have an idea on how to improve our website?
Please write us.
© 2025 De Gruyter Brill
Downloaded on 13.9.2025 from https://www.degruyterbrill.com/document/doi/10.1515/secm-2024-0048/html
Scroll to top button