-
Al-Si alloys have been widely used in automotive, aerospace, electronics and communication industries due to their excellent castability, low thermal expansion, and good wear and corrosion resistance. However, the presence of coarse eutectic Si often results in relatively low thermal conductivity. With the rapid development of the electronics and communication industries, the demand for thermal conductivity and mechanical properties of materials is increasing. In this study, the effects of heat treatment and minor Mg addition on the microstructure, mechanical properties, and thermal conductivity of Al-7Si alloys were systematically investigated.
The results indicate that heat treatment at 300℃ after solution treatment promotes the spheroidization of eutectic Si and reduces the solid solubility of solute atoms in the aluminum matrix, thereby enhancing the thermal conductivity and reducing the hardness of the Al-7Si alloy. The three-step heat treatment process (solution treatment + 300℃ treatment + 180℃ treatment) not only facilitates the spheroidization of eutectic Si, but also induces the precipitation of nanoscale (Mg, Si) strengthening phases and further decreases the solid solubility of solute elements in the Al-7Si alloy with 0.4%Mg addition. After the three-step heat treatment, the thermal conductivity and microhardness of the Al-7Si-0.4Mg alloy reach to 189 W/(m·K) and 73.5 HV, respectively. Compared to the as-cast Al-7Si alloy, they are increased by 11.2% and 62.6% respectively.
According to the Wiedemann-Franz law and the Matthiessen-Fleming rule, the primary factors influencing the thermal conductivity of alloys are solute atoms in solid solution and secondary phases. In this study, a three-step heat treatment process was used to transform the plate-like eutectic silicon in the Al-7Si-0.4Mg alloy into fine spherical particles. Additionally, micrometer-sized silicon particles and nanoscale (Mg, Si) precipitates were induced within the alloy matrix. This microstructural modification simultaneously enhanced both the thermal conductivity and mechanical properties of the alloy. Our work is expected to inspire the design of Al-Si alloy with high strength and high conductivity.-
Keywords:
- Al-Si alloy /
- Microstructure /
- Thermal conductivity /
- Mechanical property
-
[1] Liu J A, Xie S S 2004 Application and technical development of aluminum alloy materials (Beijing: Metallurgical Industry Press) p139(in Chinese) [刘静安，谢水生2004铝合金材料的应用与技术开发(北京:冶金工业出版社)第139页]
[2] Zhang J X, Zhang M J, Li H F, Gu H Z, Chen D, Zhang C H, Tian Y F, Wang E J, Mu Q N 2024 J. Mater. Sci. Technol. 17648
[3] Gao X P, Li X T, Qie X W, Wu Y P, Li X M, Li T J 2007 Acta Phys. Sin. 561188(in Chinese) [高学鹏，李新涛，郄喜望，吴亚萍，李喜孟，李廷举2007物理学报561188]
[4] Zhao Z Y, Li D X, Yan X R, Chen Y, Jia Z, Zhang D Q, Han M X, Wang X, Liu G L, Liu X F, Liu S D 2024 J. Mater. Sci. Technol. 18944
[5] Zhang R Y, Li J C,Sha J H, Li J K 2024 T. Mater. Heat Treat. 451 (in Chinese) [张瑞英，李继承，沙君浩，李家康2024材料热处理学报4501]
[6] Gan J Q, Huang Y J, Du J, Wen C, Liu J 2020 Mater. Res. Express 7086501
[7] Zhang L L, Ji Z W, Zhao J Z, He J, Jiang H X 2023 Acta Metall. Sin. 5911(in Chinese) [张丽丽，吉宗威，赵九洲，何杰，江鸿翔2023金属学报5911]
[8] Zheng Q J, Ye Z F, Jiang H X, Lu M, Zhang L L, Zhao J Z 2021 Acta Metall. Sin. 571 (in Chinese) [郑秋菊，叶中飞，江鸿翔，卢明，张丽丽，赵九洲2021金属学报571]
[9] Zheng Q J, Zhang L L, Jiang H X, Zhao J Z, He J 2020 J. Mater. Sci. Technol. 47142
[10] Qi Z Y, Wang B, Jiang H X, Zhang L L, He J 2024 Acta Phys. Sin. 73076401(in Chinese) [戚忠乙，王博，江鸿翔，张丽丽，何杰2024物理学报73076401]
[11] Dong X X, He L J, Li P J 2014 J. Alloy. Compd. 61220
[12] Chen Z W, Lei Y M, Zhang H F. 2011 J. Alloy. Compd. 50927
[13] Zhan M Y, Chen Z H, Yan H G 2008 J. Mater. Process. Technol. 202269
[14] Taghavi F, Saghafian H, Kharrazi Y H K 2009 Mater. Des. 30115
[15] Mao W M, Zhao W M, Cui C L, Zhong X Y 1999 Acta Metall. Sin. 35971(in Chinese) [毛卫民，赵爱民，崔成林，钟雪友1999金属学报35971]
[16] Jin C K, Bolouri A, Kang C G. 2013 Metall. Mater. Trans. B 451068
[17] Wang J Y, Wang B J, Huang L F. 2017 J. Mater. Sci. Technol. 331235
[18] Cheng W, Liu C Y, Huang H F, Zhang L, Zhang B, Shi L 2021 Mater. Charact. 178111278
[19] Torres L V, Zoqui E J 2024 Int. J. Met. 18769
[20] Son H W, Lee J Y, Cho Y H, Jang J I, Kim S B, Lee J M 2023 J. Alloy. Compd. 960170982.
[21] Bakhtiyarov S I, Overfelt R A, Teodorescu S G 2001 J. Mater. Sci. 364643
[22] Liu Q Y, Li Q C, Zhu P Y 1987 Mater. Sci. Technol. 665(in Chinese) [刘启阳， 李庆春，朱培钺1987金属科学与工艺6 65]
[23] Wang A, Sheng Y F, Bao H 2024 Acta Phys. Sin. 73037201(in Chinese) [王奥，盛宇飞，鲍华2024物理学报73037201]
[24] Hou J P, Wang Q, Zhang Z J, Tian Y Z, Wu X M, Yang H J, Li X W, Zhang Z F 2017 Mater. Des. 132148
[25] Wang W Y, Pan Q L, Jiang F Q, Yu Y, Lin G, Wang X D, Ye J, Pan D C, Huang Z Q, Xiang S Q, Li J, Liu B 2022 J. Alloy. Compd. 895162654
[26] Zhang J Y, Peng J. 2023 J. Mater. Res. 381488
[27] Raeisinia B, Poole W J, Lloyd D J 2006 Mater. Sci. Eng. A 420245
[28] Chen J K, Hung H Y, Wang C F, Tang N K 2015 J. Mater. Sci. 505630
[29] Weng W P, Nagaumi H, Sheng X D, Fan W Z, Chen X C, Wang X N 2019 Light Metals Symposium at the 148th TMS Annual Meeting San Antonio, TX, March 10-12, 2019 p193
[30] Li S S, Tang J L, Zeng D B 2008 Spec. Cast. Nonferrous Alloys 011704(in Chinese) [李双寿，唐靖林，曾大本2008特种铸造及有色合金011704]
[31] Sauvage X, Bobruk E V, Murashkin M Y, Nasedkina Y, Enikeev N A, Valiev R Z 2015 Acta Mater. 98355
[32] Li X S, Cai A H, Chen H, Zeng J J 2009 Hot Work. Technol. 38117(in Chinese) [李小松，蔡安辉，陈华，曾纪杰2009热加工工艺38117]
Metrics
- Abstract views: 91
- PDF Downloads: 0
- Cited By: 0
下载:
