Impact of Melt Refining on Secondary Al-Si Alloys’ Microstructure and Tensile Mechanical Performance
Abstract
1. Introduction
2. Experimental
2.1. Materials
2.2. Experimental Procedure
2.3. Characterization Devices
3. Results and Discussion
3.1. Melt Refining
3.1.1. The Effect of Standing Time and a Single Additive
3.1.2. Oxidative Removal of Mg and the Effect of Composite Addition
3.2. Analysis of Secondary Al-Si Alloy Slag
3.3. Characterization
3.3.1. OM Analysis
3.3.2. SEM-EDS Analysis
3.3.3. Mechanical Performance
3.3.4. EBSD Analysis
3.3.5. Fracture Analysis
3.4. Exploration of Refining Principles
4. Conclusions
- (1)
- The composite additive achieved removal efficiencies of 89.9% Mg, 68.9% Ti, and 61.5% V. The effect of aluminum–boron master alloy on the elimination of impurity elements Ti and V can be improved by the use of fluxing. Grain refinement and organization flaws can be improved by adding aluminum boron master alloy and fluxing;
- (2)
- The amalgamation of fluxing and aluminum–boron master alloy can modify the grain orientation distribution of secondary Al-Si alloys and augment their geometrical dislocation density, thus improving their mechanical properties;
- (3)
- The tensile properties were considerably enhanced by the use of 0.6 wt.% aluminum–boron master alloy and 0.5 wt.% fluxing. The yield strength was 87.5 MPa, the elongation at break was 10.6%, and the tensile strength was 140.4 MPa, which was 28.7% greater than the raw material.
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
Mg | Magnesium |
Ti | Titanium |
V | Vanadium |
IPF | Inverse Pole Figure |
KAM | Kernel Average Misorientation |
GND | Geometrically Necessary Dislocation |
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Element | Al | Si | Fe | Cu | Mn | Mg | Ti | V |
---|---|---|---|---|---|---|---|---|
Content wt.% | 96.8 | 1.94 | 0.736 | 0.212 | 0.0516 | 0.0188 | 0.0225 | 0.0221 |
Element | Al | Si | Fe | Cu | Mn | Mg | Ti | V |
---|---|---|---|---|---|---|---|---|
Content wt.% | 96.9 | 1.93 | 0.723 | 0.209 | 0.0508 | 0.0019 | 0.0070 | 0.0085 |
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Gu, W.; Jin, H.; Wang, X.; Jiang, J. Impact of Melt Refining on Secondary Al-Si Alloys’ Microstructure and Tensile Mechanical Performance. Metals 2025, 15, 556. https://doi.org/10.3390/met15050556
Gu W, Jin H, Wang X, Jiang J. Impact of Melt Refining on Secondary Al-Si Alloys’ Microstructure and Tensile Mechanical Performance. Metals. 2025; 15(5):556. https://doi.org/10.3390/met15050556
Chicago/Turabian StyleGu, Wei, Huixin Jin, Xue Wang, and Jiajun Jiang. 2025. "Impact of Melt Refining on Secondary Al-Si Alloys’ Microstructure and Tensile Mechanical Performance" Metals 15, no. 5: 556. https://doi.org/10.3390/met15050556
APA StyleGu, W., Jin, H., Wang, X., & Jiang, J. (2025). Impact of Melt Refining on Secondary Al-Si Alloys’ Microstructure and Tensile Mechanical Performance. Metals, 15(5), 556. https://doi.org/10.3390/met15050556