Journal of Ultrafine Grained and Nanostructured Materials

Journal of Ultrafine Grained and Nanostructured Materials

Improved mechanical properties of in-situ Al-Mg2Si composites via Sr addition

Document Type : Research Paper

Authors
Mohammad Sokouti
Hamidreza Pourkhodkar Lomer
Massoud Emamy
Hamed Mirzadeh
School Of Metallurgy And Materials, College Of Engineering, University Of Tehran, Tehran, Iran
10.22059/jufgnsm.2026.01.01
Abstract
Effects of strontium addition to the Al-Mg2Si composite on the microstructure, phase formation, and improvement of the mechanical properties in the wrought condition were investigated. Accordingly, 0, 1, 2, 3, and 5 wt.% Sr was added to the Al-15Mg2Si composite. Results revealed that the optimum Sr addition up to 2 wt.% leads to the modification of Mg2Si particles. Moreover, the emergence of Al2Si2Sr particles resulted in the development of a hybrid composite microstructure. These microstructural modifications, combined with the extrusion process, resulted in the improvement of mechanical properties, in terms of yield stress, ultimate tensile strength, total elongation, and tensile toughness. For instance, tensile toughness, as a measure of the strength-ductility synergy, for the Sr addition of 2 wt.% showed 30% improvement compared to the base composite. However, higher Sr additions of 3 and 5 wt.% resulted in the formation of coarse needle-shaped Al2Si2Sr and Al4Sr particles, which resulted in poor ductility and work-hardening behavior. Moreover, the significant reduction in the amount of Mg2Si phase at high Sr additions was found to be in contrast to the idea of hybrid composite formation. Accordingly, the present work sheds light on the development of hybrid Al-Mg2Si/Al2Si2Sr composites via optimum Sr addition to the Al-Mg2Si composite for the improvement of mechanical behavior.
Keywords
Hybrid metal-matrix composites
Solidification and casting
Modification
Thermomechanical processing
Tensile properties
  1. Gong, Y., Malik, A., Wang, Y., Feng, S., Zhao, D. and Yuan, C., 2022. Numerical simulation and experimental studies of gas pressure infiltration Al-356/SiC composites. Metals, 12(12), p.2150.
  2. Mohammad Nejad Fard, N., Mirzadeh, H., Mohammad, R. and Cabrera, J.M., 2017. Accumulative roll bonding of aluminum/stainless steel sheets. Journal of Ultrafine Grained and Nanostructured Materials, 50(1), pp.1-5.
  3. Rezayat, M., Parsa, M.H., Mirzadeh, H. and Cabrera, J.M., 2018. Microstructural investigation of Al-Mg/B4C composite deformed at elevated temperature. Journal of Alloys and Compounds, 763, pp.643-651.
  4. Emamy, M., Pourbahari, B., Malekan, M. and Emami, K., 2016. Effects of Mg2Sn intermetallic on the microstructure and tensile properties of Al–15% Mg2Si–X% Sn composite. Journal of Materials Research, 31(24), pp.3891-3899.
  5. Pramod, S.L., Bakshi, S.R. and Murty, B.S., 2015. Aluminum-based cast in situ composites: a review. Journal of Materials Engineering and Performance, 24(6), pp.2185-2207.
  6. Tjong, S.C. and Ma, Z.Y., 2000. Microstructural and mechanical characteristics of in situ metal matrix composites. Materials Science and Engineering: R: Reports, 29(3-4), pp.49-113.
  7. Li, C., Wu, Y.Y., Li, H. and Liu, X.F., 2011. Morphological evolution and growth mechanism of primary Mg2Si phase in Al–Mg2Si alloys. Acta Materialia, 59(3), pp.1058-1067.
  8. Safary, E., Taghiabadi, R. and Ghoncheh, M.H., 2022. Mechanical properties of Al-15Mg2Si composites prepared under different solidification cooling rates. International Journal of Minerals, Metallurgy and Materials, 29(6), pp.1249-1260.
  9. Alizadeh, R. and Mahmudi, R., 2011. Effects of Sb addition on the modification of Mg2Si particles and high-temperature mechanical properties of cast Mg–4Zn–2Si alloy. Journal of alloys and compounds, 509(37), pp.9195-9199.
  10. Jafari Nodooshan, H.R., Liu, W., Wu, G., Bahrami, A., Pech-Canul, M.I. and Emamy, M., 2014. Mechanical and tribological characterization of Al-Mg2Si composites after yttrium addition and heat treatment. Journal of Materials Engineering and Performance, 23(4), pp.1146-1156.
  11. Wang, K.Y., Zhao, R.D., Wu, F.F., Wu, X.F., Chen, M.H., Xiang, J. and Chen, S.H., 2020. Improving microstructure and mechanical properties of hypoeutectic Al-Mg2Si alloy by Gd addition. Journal of Alloys and Compounds, 813, p.152178.
  12. Bo, R.E.N. and ZHANG, T.Q., 2010. Effect of Sb on microstructure and mechanical properties of Mg2Si/Al-Si composites. Transactions of Nonferrous Metals Society of China, 20(8), pp.1367-1373.
  13. Qin, Q.D., Zhao, Y.G., Zhou, W. and Cong, P.J., 2007. Effect of phosphorus on microstructure and growth manner of primary Mg2Si crystal in Mg2Si/Al composite. Materials Science and Engineering: A, 447(1-2), pp.186-191.
  14. Hadian, R., Emamy, M., Varahram, N. and Nemati, N., 2008. The effect of Li on the tensile properties of cast Al–Mg2Si metal matrix composite. Materials Science and Engineering: A, 490(1-2), pp.250-257.
  15. Qin, Q.D., Zhao, Y.G., Liu, C., Cong, P.J. and Zhou, W., 2008. Strontium modification and formation of cubic primary Mg2Si crystals in Mg2Si/Al composite. Journal of Alloys and Compounds, 454(1-2), pp.142-146.
  16. Wang, D., Zhang, H., Han, X., Shao, B., Li, L. and Cui, J., 2017. The analysis of strontium modification on microstructure and mechanical properties of Al-25% Mg2Si in situ composite. Journal of Materials Engineering and Performance, 26(9), pp.4415-4423.
  17. Ravishankar, B., Nayak, S.K. and Kader, M.A., 2019. Hybrid composites for automotive applications–A review. Journal of Reinforced Plastics and Composites, 38(18), pp.835-845.
  18. Ko, E.C., Lee, B.K., Yoo, H.S., Kim, Y.H., Son, H.T. and Lee, K., 2025. Influence of Sr content on the microstructure, mechanical properties, and electrical conductivity of Al-Si-Mg alloy. Current Applied Physics, 74, pp.54-60.
  19. Ghandvar, H., Idris, M.H. and Ahmad, N., 2018. Effect of hot extrusion on microstructural evolution and tensile properties of Al-15% Mg2Si-xGd in-situ composites. Journal of Alloys and Compounds, 751, pp.370-390.
  20. Moazami, M.R., Razaghian, A., Mirzadeh, H. and Emamy, M., 2022. Tailoring the mechanical properties of hypereutectic in situ Al–Mg2Si composites via hybrid TiB2 reinforcement and hot extrusion. Archives of Civil and Mechanical Engineering, 22(2), p.87.
  21. Shafieizad, A.H., Zarei-Hanzaki, A., Abedi, H.R. and Al-Fadhalah, K.J., 2015. The Mg2Si phase evolution during thermomechanical processing of in-situ aluminum matrix macro-composite. Materials Science and Engineering: A, 644, pp.310-317.
  22. Safary, E., Taghiabadi, R., Ghoncheh, M.H., Emami, M. and Yazdi, M.S., 2024. Effect of solidification cooling rate on corrosion behavior of Al-15Mg2Si composites. Materials Today Communications, 38, p.107948.
  23. Hesami, L., Taghiabadi, R. and Ghoncheh, M.H., 2022. Study on the modification effect of copper on Al–15Mg2Si composite. Materials Chemistry and Physics, 276, p.125323.
  24. Zhang, J., Fan, Z., Wang, Y.Q. and Zhou, B.L., 2001. Equilibrium pseudobinary Al–Mg2Si phase diagram. Materials Science and Technology, 17(5), pp.494-496.
  25. Seth, P.P., Parkash, O. and Kumar, D., 2020. Structure and mechanical behavior of in situ developed Mg2Si phase in magnesium and aluminum alloys–a review. RSC advances, 10(61), pp.37327-37345.
  26. Khorshidi, R., Mahmudi, R. and Honarbakhsh-Raouf, A., 2016. Compressive creep behavior of a cast Al–15Mg2Si in situ composite. Materials Science and Engineering: A, 668, pp.112-119.
  27. Moazami, M.R., Razaghian, A., Moharami, A., Mirzadeh, H. and Emamy, M., 2022. Enhancing the elevated temperatures tribological properties of Al–Mg2Si composites by in-situ addition of Ti-based intermetallics and hot working. Journal of Materials Research and Technology, 21, pp.1381-1394.
  28. Saunders, N., Guo, U.K.Z., Li, X., Miodownik, A.P. and Schillé, J.P., 2003. Using JMatPro to model materials properties and behavior. JOM, 55(12), pp.60-65.
  29. Zamani, R., Mirzadeh, H. and Emamy, M., 2018. Mechanical properties of a hot deformed Al-Mg2Si in-situ composite. Materials Science and Engineering: A, 726, pp.10-17.
  30. Zamani, R., Mirzadeh, H. and Emamy, M., 2018. Magnificent grain refinement of Al-Mg2Si composite by hot rolling. Journal of Ultrafine Grained and Nanostructured Materials, 51(1), pp.71-76.
  31. Sarkari Khorrami, M., Saito, N. and Miyashita, Y., 2019. Texture and strain-induced abnormal grain growth in cryogenic friction stir processing of severely deformed aluminum alloy. Materials Characterization, 151, pp.378-389.
  32. Sabbaghian, M., Fakhar, N., Mola, J., Mahmudi, R., Sidor, J.J., Mukhtarova, K. and Gubicza, J., 2025. Serrated Shear Flow in AA5083 Alloy Refined by Dual Equal Channel Lateral Extrusion Process. Metals and Materials International, pp.1-14.
  33. Sarkari Khorrami, M., Kazeminezhad, M., Miyashita, Y., Saito, N. and Kokabi, A.H., 2017. Influence of ambient and cryogenic temperature on friction stir processing of severely deformed aluminum with SiC nanoparticles. Journal of Alloys and Compounds, 718, pp.361-372.
  34. Fakhar, N., Khademi, E., Sabbaghian, M., Momeni, A., Fereshteh-Saniee, F., Nagy, P., Szabo, A. and Gubicza, J., 2023. Microstructure and hot shear deformation behavior of a fine-grained AA5083 aluminum alloy. Materials Chemistry and Physics, 294, p.126976.
  35. Yeganeh, S.V., Razaghian, A. and Emamy, M., 2013. The influence of Cu–15P master alloy on the microstructure and tensile properties of Al–25 wt% Mg2Si composite before and after hot-extrusion. Materials Science and Engineering: A, 566, pp.1-7.
  36. Sharifian, K., Emamy, M., Tavighi, K. and Vaziri Yeganeh, S.E., 2014. Microstructures and tensile properties of hot-extruded Al matrix composites containing different amounts of Al4Sr. Metallurgical and Materials Transactions A, 45(12), pp.5344-5350.
Journal of Ultrafine Grained and Nanostructured Materials
Volume 59, Issue 1
June 2026
Pages 1-10

  • Receive Date 11 November 2025
  • Revise Date 07 February 2026
  • Accept Date 14 February 2026